granicus.if.org Git - postgresql/blob - src/backend/utils/misc/guc.c

   1 /*--------------------------------------------------------------------
   2  * guc.c
   3  *
   4  * Support for grand unified configuration scheme, including SET
   5  * command, configuration file, and command line options.
   6  * See src/backend/utils/misc/README for more information.
   7  *
   8  *
   9  * Copyright (c) 2000-2012, PostgreSQL Global Development Group
  10  * Written by Peter Eisentraut <peter_e@gmx.net>.
  11  *
  12  * IDENTIFICATION
  13  *        src/backend/utils/misc/guc.c
  14  *
  15  *--------------------------------------------------------------------
  16  */
  17 #include "postgres.h"
  18
  19 #include <ctype.h>
  20 #include <float.h>
  21 #include <math.h>
  22 #include <limits.h>
  23 #include <unistd.h>
  24 #include <sys/stat.h>
  25 #ifdef HAVE_SYSLOG
  26 #include <syslog.h>
  27 #endif
  28
  29 #include "access/gin.h"
  30 #include "access/transam.h"
  31 #include "access/twophase.h"
  32 #include "access/xact.h"
  33 #include "catalog/namespace.h"
  34 #include "commands/async.h"
  35 #include "commands/prepare.h"
  36 #include "commands/vacuum.h"
  37 #include "commands/variable.h"
  38 #include "commands/trigger.h"
  39 #include "funcapi.h"
  40 #include "libpq/auth.h"
  41 #include "libpq/be-fsstubs.h"
  42 #include "libpq/pqformat.h"
  43 #include "miscadmin.h"
  44 #include "optimizer/cost.h"
  45 #include "optimizer/geqo.h"
  46 #include "optimizer/paths.h"
  47 #include "optimizer/planmain.h"
  48 #include "parser/parse_expr.h"
  49 #include "parser/parse_type.h"
  50 #include "parser/parser.h"
  51 #include "parser/scansup.h"
  52 #include "pgstat.h"
  53 #include "postmaster/autovacuum.h"
  54 #include "postmaster/bgwriter.h"
  55 #include "postmaster/postmaster.h"
  56 #include "postmaster/syslogger.h"
  57 #include "postmaster/walwriter.h"
  58 #include "replication/syncrep.h"
  59 #include "replication/walreceiver.h"
  60 #include "replication/walsender.h"
  61 #include "storage/bufmgr.h"
  62 #include "storage/standby.h"
  63 #include "storage/fd.h"
  64 #include "storage/predicate.h"
  65 #include "tcop/tcopprot.h"
  66 #include "tsearch/ts_cache.h"
  67 #include "utils/builtins.h"
  68 #include "utils/bytea.h"
  69 #include "utils/guc_tables.h"
  70 #include "utils/memutils.h"
  71 #include "utils/pg_locale.h"
  72 #include "utils/plancache.h"
  73 #include "utils/portal.h"
  74 #include "utils/ps_status.h"
  75 #include "utils/snapmgr.h"
  76 #include "utils/tzparser.h"
  77 #include "utils/xml.h"
  78
  79 #ifndef PG_KRB_SRVTAB
  80 #define PG_KRB_SRVTAB ""
  81 #endif
  82 #ifndef PG_KRB_SRVNAM
  83 #define PG_KRB_SRVNAM ""
  84 #endif
  85
  86 #define CONFIG_FILENAME "postgresql.conf"
  87 #define HBA_FILENAME    "pg_hba.conf"
  88 #define IDENT_FILENAME  "pg_ident.conf"
  89
  90 #ifdef EXEC_BACKEND
  91 #define CONFIG_EXEC_PARAMS "global/config_exec_params"
  92 #define CONFIG_EXEC_PARAMS_NEW "global/config_exec_params.new"
  93 #endif
  94
  95 /* upper limit for GUC variables measured in kilobytes of memory */
  96 /* note that various places assume the byte size fits in a "long" variable */
  97 #if SIZEOF_SIZE_T > 4 && SIZEOF_LONG > 4
  98 #define MAX_KILOBYTES   INT_MAX
  99 #else
 100 #define MAX_KILOBYTES   (INT_MAX / 1024)
 101 #endif
 102
 103 /*
 104  * Note: MAX_BACKENDS is limited to 2^23-1 because inval.c stores the
 105  * backend ID as a 3-byte signed integer.  Even if that limitation were
 106  * removed, we still could not exceed INT_MAX/4 because some places compute
 107  * 4*MaxBackends without any overflow check.  This is rechecked in
 108  * check_maxconnections, since MaxBackends is computed as MaxConnections
 109  * plus autovacuum_max_workers plus one (for the autovacuum launcher).
 110  */
 111 #define MAX_BACKENDS    0x7fffff
 112
 113 #define KB_PER_MB (1024)
 114 #define KB_PER_GB (1024*1024)
 115
 116 #define MS_PER_S 1000
 117 #define S_PER_MIN 60
 118 #define MS_PER_MIN (1000 * 60)
 119 #define MIN_PER_H 60
 120 #define S_PER_H (60 * 60)
 121 #define MS_PER_H (1000 * 60 * 60)
 122 #define MIN_PER_D (60 * 24)
 123 #define S_PER_D (60 * 60 * 24)
 124 #define MS_PER_D (1000 * 60 * 60 * 24)
 125
 126 /* XXX these should appear in other modules' header files */
 127 extern bool Log_disconnections;
 128 extern int      CommitDelay;
 129 extern int      CommitSiblings;
 130 extern char *default_tablespace;
 131 extern char *temp_tablespaces;
 132 extern bool synchronize_seqscans;
 133 extern bool fullPageWrites;
 134 extern int      ssl_renegotiation_limit;
 135 extern char *SSLCipherSuites;
 136
 137 #ifdef TRACE_SORT
 138 extern bool trace_sort;
 139 #endif
 140 #ifdef TRACE_SYNCSCAN
 141 extern bool trace_syncscan;
 142 #endif
 143 #ifdef DEBUG_BOUNDED_SORT
 144 extern bool optimize_bounded_sort;
 145 #endif
 146
 147 static int      GUC_check_errcode_value;
 148
 149 /* global variables for check hook support */
 150 char       *GUC_check_errmsg_string;
 151 char       *GUC_check_errdetail_string;
 152 char       *GUC_check_errhint_string;
 153
 154
 155 static void set_config_sourcefile(const char *name, char *sourcefile,
 156                                           int sourceline);
 157 static bool call_bool_check_hook(struct config_bool * conf, bool *newval,
 158                                          void **extra, GucSource source, int elevel);
 159 static bool call_int_check_hook(struct config_int * conf, int *newval,
 160                                         void **extra, GucSource source, int elevel);
 161 static bool call_real_check_hook(struct config_real * conf, double *newval,
 162                                          void **extra, GucSource source, int elevel);
 163 static bool call_string_check_hook(struct config_string * conf, char **newval,
 164                                            void **extra, GucSource source, int elevel);
 165 static bool call_enum_check_hook(struct config_enum * conf, int *newval,
 166                                          void **extra, GucSource source, int elevel);
 167
 168 static bool check_log_destination(char **newval, void **extra, GucSource source);
 169 static void assign_log_destination(const char *newval, void *extra);
 170
 171 #ifdef HAVE_SYSLOG
 172 static int      syslog_facility = LOG_LOCAL0;
 173 #else
 174 static int      syslog_facility = 0;
 175 #endif
 176
 177 static void assign_syslog_facility(int newval, void *extra);
 178 static void assign_syslog_ident(const char *newval, void *extra);
 179 static void assign_session_replication_role(int newval, void *extra);
 180 static bool check_temp_buffers(int *newval, void **extra, GucSource source);
 181 static bool check_phony_autocommit(bool *newval, void **extra, GucSource source);
 182 static bool check_debug_assertions(bool *newval, void **extra, GucSource source);
 183 static bool check_bonjour(bool *newval, void **extra, GucSource source);
 184 static bool check_ssl(bool *newval, void **extra, GucSource source);
 185 static bool check_stage_log_stats(bool *newval, void **extra, GucSource source);
 186 static bool check_log_stats(bool *newval, void **extra, GucSource source);
 187 static bool check_canonical_path(char **newval, void **extra, GucSource source);
 188 static bool check_timezone_abbreviations(char **newval, void **extra, GucSource source);
 189 static void assign_timezone_abbreviations(const char *newval, void *extra);
 190 static void pg_timezone_abbrev_initialize(void);
 191 static const char *show_archive_command(void);
 192 static void assign_tcp_keepalives_idle(int newval, void *extra);
 193 static void assign_tcp_keepalives_interval(int newval, void *extra);
 194 static void assign_tcp_keepalives_count(int newval, void *extra);
 195 static const char *show_tcp_keepalives_idle(void);
 196 static const char *show_tcp_keepalives_interval(void);
 197 static const char *show_tcp_keepalives_count(void);
 198 static bool check_maxconnections(int *newval, void **extra, GucSource source);
 199 static void assign_maxconnections(int newval, void *extra);
 200 static bool check_autovacuum_max_workers(int *newval, void **extra, GucSource source);
 201 static void assign_autovacuum_max_workers(int newval, void *extra);
 202 static bool check_effective_io_concurrency(int *newval, void **extra, GucSource source);
 203 static void assign_effective_io_concurrency(int newval, void *extra);
 204 static void assign_pgstat_temp_directory(const char *newval, void *extra);
 205 static bool check_application_name(char **newval, void **extra, GucSource source);
 206 static void assign_application_name(const char *newval, void *extra);
 207 static const char *show_unix_socket_permissions(void);
 208 static const char *show_log_file_mode(void);
 209
 210 static char *config_enum_get_options(struct config_enum * record,
 211                                                 const char *prefix, const char *suffix,
 212                                                 const char *separator);
 213
 214
 215 /*
 216  * Options for enum values defined in this module.
 217  *
 218  * NOTE! Option values may not contain double quotes!
 219  */
 220
 221 static const struct config_enum_entry bytea_output_options[] = {
 222         {"escape", BYTEA_OUTPUT_ESCAPE, false},
 223         {"hex", BYTEA_OUTPUT_HEX, false},
 224         {NULL, 0, false}
 225 };
 226
 227 /*
 228  * We have different sets for client and server message level options because
 229  * they sort slightly different (see "log" level)
 230  */
 231 static const struct config_enum_entry client_message_level_options[] = {
 232         {"debug", DEBUG2, true},
 233         {"debug5", DEBUG5, false},
 234         {"debug4", DEBUG4, false},
 235         {"debug3", DEBUG3, false},
 236         {"debug2", DEBUG2, false},
 237         {"debug1", DEBUG1, false},
 238         {"log", LOG, false},
 239         {"info", INFO, true},
 240         {"notice", NOTICE, false},
 241         {"warning", WARNING, false},
 242         {"error", ERROR, false},
 243         {"fatal", FATAL, true},
 244         {"panic", PANIC, true},
 245         {NULL, 0, false}
 246 };
 247
 248 static const struct config_enum_entry server_message_level_options[] = {
 249         {"debug", DEBUG2, true},
 250         {"debug5", DEBUG5, false},
 251         {"debug4", DEBUG4, false},
 252         {"debug3", DEBUG3, false},
 253         {"debug2", DEBUG2, false},
 254         {"debug1", DEBUG1, false},
 255         {"info", INFO, false},
 256         {"notice", NOTICE, false},
 257         {"warning", WARNING, false},
 258         {"error", ERROR, false},
 259         {"log", LOG, false},
 260         {"fatal", FATAL, false},
 261         {"panic", PANIC, false},
 262         {NULL, 0, false}
 263 };
 264
 265 static const struct config_enum_entry intervalstyle_options[] = {
 266         {"postgres", INTSTYLE_POSTGRES, false},
 267         {"postgres_verbose", INTSTYLE_POSTGRES_VERBOSE, false},
 268         {"sql_standard", INTSTYLE_SQL_STANDARD, false},
 269         {"iso_8601", INTSTYLE_ISO_8601, false},
 270         {NULL, 0, false}
 271 };
 272
 273 static const struct config_enum_entry log_error_verbosity_options[] = {
 274         {"terse", PGERROR_TERSE, false},
 275         {"default", PGERROR_DEFAULT, false},
 276         {"verbose", PGERROR_VERBOSE, false},
 277         {NULL, 0, false}
 278 };
 279
 280 static const struct config_enum_entry log_statement_options[] = {
 281         {"none", LOGSTMT_NONE, false},
 282         {"ddl", LOGSTMT_DDL, false},
 283         {"mod", LOGSTMT_MOD, false},
 284         {"all", LOGSTMT_ALL, false},
 285         {NULL, 0, false}
 286 };
 287
 288 static const struct config_enum_entry isolation_level_options[] = {
 289         {"serializable", XACT_SERIALIZABLE, false},
 290         {"repeatable read", XACT_REPEATABLE_READ, false},
 291         {"read committed", XACT_READ_COMMITTED, false},
 292         {"read uncommitted", XACT_READ_UNCOMMITTED, false},
 293         {NULL, 0}
 294 };
 295
 296 static const struct config_enum_entry session_replication_role_options[] = {
 297         {"origin", SESSION_REPLICATION_ROLE_ORIGIN, false},
 298         {"replica", SESSION_REPLICATION_ROLE_REPLICA, false},
 299         {"local", SESSION_REPLICATION_ROLE_LOCAL, false},
 300         {NULL, 0, false}
 301 };
 302
 303 static const struct config_enum_entry syslog_facility_options[] = {
 304 #ifdef HAVE_SYSLOG
 305         {"local0", LOG_LOCAL0, false},
 306         {"local1", LOG_LOCAL1, false},
 307         {"local2", LOG_LOCAL2, false},
 308         {"local3", LOG_LOCAL3, false},
 309         {"local4", LOG_LOCAL4, false},
 310         {"local5", LOG_LOCAL5, false},
 311         {"local6", LOG_LOCAL6, false},
 312         {"local7", LOG_LOCAL7, false},
 313 #else
 314         {"none", 0, false},
 315 #endif
 316         {NULL, 0}
 317 };
 318
 319 static const struct config_enum_entry track_function_options[] = {
 320         {"none", TRACK_FUNC_OFF, false},
 321         {"pl", TRACK_FUNC_PL, false},
 322         {"all", TRACK_FUNC_ALL, false},
 323         {NULL, 0, false}
 324 };
 325
 326 static const struct config_enum_entry xmlbinary_options[] = {
 327         {"base64", XMLBINARY_BASE64, false},
 328         {"hex", XMLBINARY_HEX, false},
 329         {NULL, 0, false}
 330 };
 331
 332 static const struct config_enum_entry xmloption_options[] = {
 333         {"content", XMLOPTION_CONTENT, false},
 334         {"document", XMLOPTION_DOCUMENT, false},
 335         {NULL, 0, false}
 336 };
 337
 338 /*
 339  * Although only "on", "off", and "safe_encoding" are documented, we
 340  * accept all the likely variants of "on" and "off".
 341  */
 342 static const struct config_enum_entry backslash_quote_options[] = {
 343         {"safe_encoding", BACKSLASH_QUOTE_SAFE_ENCODING, false},
 344         {"on", BACKSLASH_QUOTE_ON, false},
 345         {"off", BACKSLASH_QUOTE_OFF, false},
 346         {"true", BACKSLASH_QUOTE_ON, true},
 347         {"false", BACKSLASH_QUOTE_OFF, true},
 348         {"yes", BACKSLASH_QUOTE_ON, true},
 349         {"no", BACKSLASH_QUOTE_OFF, true},
 350         {"1", BACKSLASH_QUOTE_ON, true},
 351         {"0", BACKSLASH_QUOTE_OFF, true},
 352         {NULL, 0, false}
 353 };
 354
 355 /*
 356  * Although only "on", "off", and "partition" are documented, we
 357  * accept all the likely variants of "on" and "off".
 358  */
 359 static const struct config_enum_entry constraint_exclusion_options[] = {
 360         {"partition", CONSTRAINT_EXCLUSION_PARTITION, false},
 361         {"on", CONSTRAINT_EXCLUSION_ON, false},
 362         {"off", CONSTRAINT_EXCLUSION_OFF, false},
 363         {"true", CONSTRAINT_EXCLUSION_ON, true},
 364         {"false", CONSTRAINT_EXCLUSION_OFF, true},
 365         {"yes", CONSTRAINT_EXCLUSION_ON, true},
 366         {"no", CONSTRAINT_EXCLUSION_OFF, true},
 367         {"1", CONSTRAINT_EXCLUSION_ON, true},
 368         {"0", CONSTRAINT_EXCLUSION_OFF, true},
 369         {NULL, 0, false}
 370 };
 371
 372 /*
 373  * Although only "on", "off", "write", and "local" are documented, we
 374  * accept all the likely variants of "on" and "off".
 375  */
 376 static const struct config_enum_entry synchronous_commit_options[] = {
 377         {"local", SYNCHRONOUS_COMMIT_LOCAL_FLUSH, false},
 378         {"write", SYNCHRONOUS_COMMIT_REMOTE_WRITE, false},
 379         {"on", SYNCHRONOUS_COMMIT_ON, false},
 380         {"off", SYNCHRONOUS_COMMIT_OFF, false},
 381         {"true", SYNCHRONOUS_COMMIT_ON, true},
 382         {"false", SYNCHRONOUS_COMMIT_OFF, true},
 383         {"yes", SYNCHRONOUS_COMMIT_ON, true},
 384         {"no", SYNCHRONOUS_COMMIT_OFF, true},
 385         {"1", SYNCHRONOUS_COMMIT_ON, true},
 386         {"0", SYNCHRONOUS_COMMIT_OFF, true},
 387         {NULL, 0, false}
 388 };
 389
 390 /*
 391  * Options for enum values stored in other modules
 392  */
 393 extern const struct config_enum_entry wal_level_options[];
 394 extern const struct config_enum_entry sync_method_options[];
 395
 396 /*
 397  * GUC option variables that are exported from this module
 398  */
 399 #ifdef USE_ASSERT_CHECKING
 400 bool            assert_enabled = true;
 401 #else
 402 bool            assert_enabled = false;
 403 #endif
 404 bool            log_duration = false;
 405 bool            Debug_print_plan = false;
 406 bool            Debug_print_parse = false;
 407 bool            Debug_print_rewritten = false;
 408 bool            Debug_pretty_print = true;
 409
 410 bool            log_parser_stats = false;
 411 bool            log_planner_stats = false;
 412 bool            log_executor_stats = false;
 413 bool            log_statement_stats = false;            /* this is sort of all three
 414                                                                                                  * above together */
 415 bool            log_btree_build_stats = false;
 416 char       *event_source;
 417
 418 bool            check_function_bodies = true;
 419 bool            default_with_oids = false;
 420 bool            SQL_inheritance = true;
 421
 422 bool            Password_encryption = true;
 423
 424 int                     log_min_error_statement = ERROR;
 425 int                     log_min_messages = WARNING;
 426 int                     client_min_messages = NOTICE;
 427 int                     log_min_duration_statement = -1;
 428 int                     log_temp_files = -1;
 429 int                     trace_recovery_messages = LOG;
 430
 431 int                     temp_file_limit = -1;
 432
 433 int                     num_temp_buffers = 1024;
 434
 435 char       *data_directory;
 436 char       *ConfigFileName;
 437 char       *HbaFileName;
 438 char       *IdentFileName;
 439 char       *external_pid_file;
 440
 441 char       *pgstat_temp_directory;
 442
 443 char       *application_name;
 444
 445 int                     tcp_keepalives_idle;
 446 int                     tcp_keepalives_interval;
 447 int                     tcp_keepalives_count;
 448
 449 /*
 450  * These variables are all dummies that don't do anything, except in some
 451  * cases provide the value for SHOW to display.  The real state is elsewhere
 452  * and is kept in sync by assign_hooks.
 453  */
 454 static char *log_destination_string;
 455
 456 static char *syslog_ident_str;
 457 static bool phony_autocommit;
 458 static bool session_auth_is_superuser;
 459 static double phony_random_seed;
 460 static char *client_encoding_string;
 461 static char *datestyle_string;
 462 static char *locale_collate;
 463 static char *locale_ctype;
 464 static char *server_encoding_string;
 465 static char *server_version_string;
 466 static int      server_version_num;
 467 static char *timezone_string;
 468 static char *log_timezone_string;
 469 static char *timezone_abbreviations_string;
 470 static char *XactIsoLevel_string;
 471 static char *session_authorization_string;
 472 static int      max_function_args;
 473 static int      max_index_keys;
 474 static int      max_identifier_length;
 475 static int      block_size;
 476 static int      segment_size;
 477 static int      wal_block_size;
 478 static int      wal_segment_size;
 479 static bool integer_datetimes;
 480 static int      effective_io_concurrency;
 481
 482 /* should be static, but commands/variable.c needs to get at this */
 483 char       *role_string;
 484
 485
 486 /*
 487  * Displayable names for context types (enum GucContext)
 488  *
 489  * Note: these strings are deliberately not localized.
 490  */
 491 const char *const GucContext_Names[] =
 492 {
 493          /* PGC_INTERNAL */ "internal",
 494          /* PGC_POSTMASTER */ "postmaster",
 495          /* PGC_SIGHUP */ "sighup",
 496          /* PGC_BACKEND */ "backend",
 497          /* PGC_SUSET */ "superuser",
 498          /* PGC_USERSET */ "user"
 499 };
 500
 501 /*
 502  * Displayable names for source types (enum GucSource)
 503  *
 504  * Note: these strings are deliberately not localized.
 505  */
 506 const char *const GucSource_Names[] =
 507 {
 508          /* PGC_S_DEFAULT */ "default",
 509          /* PGC_S_DYNAMIC_DEFAULT */ "default",
 510          /* PGC_S_ENV_VAR */ "environment variable",
 511          /* PGC_S_FILE */ "configuration file",
 512          /* PGC_S_ARGV */ "command line",
 513          /* PGC_S_DATABASE */ "database",
 514          /* PGC_S_USER */ "user",
 515          /* PGC_S_DATABASE_USER */ "database user",
 516          /* PGC_S_CLIENT */ "client",
 517          /* PGC_S_OVERRIDE */ "override",
 518          /* PGC_S_INTERACTIVE */ "interactive",
 519          /* PGC_S_TEST */ "test",
 520          /* PGC_S_SESSION */ "session"
 521 };
 522
 523 /*
 524  * Displayable names for the groupings defined in enum config_group
 525  */
 526 const char *const config_group_names[] =
 527 {
 528         /* UNGROUPED */
 529         gettext_noop("Ungrouped"),
 530         /* FILE_LOCATIONS */
 531         gettext_noop("File Locations"),
 532         /* CONN_AUTH */
 533         gettext_noop("Connections and Authentication"),
 534         /* CONN_AUTH_SETTINGS */
 535         gettext_noop("Connections and Authentication / Connection Settings"),
 536         /* CONN_AUTH_SECURITY */
 537         gettext_noop("Connections and Authentication / Security and Authentication"),
 538         /* RESOURCES */
 539         gettext_noop("Resource Usage"),
 540         /* RESOURCES_MEM */
 541         gettext_noop("Resource Usage / Memory"),
 542         /* RESOURCES_DISK */
 543         gettext_noop("Resource Usage / Disk"),
 544         /* RESOURCES_KERNEL */
 545         gettext_noop("Resource Usage / Kernel Resources"),
 546         /* RESOURCES_VACUUM_DELAY */
 547         gettext_noop("Resource Usage / Cost-Based Vacuum Delay"),
 548         /* RESOURCES_BGWRITER */
 549         gettext_noop("Resource Usage / Background Writer"),
 550         /* RESOURCES_ASYNCHRONOUS */
 551         gettext_noop("Resource Usage / Asynchronous Behavior"),
 552         /* WAL */
 553         gettext_noop("Write-Ahead Log"),
 554         /* WAL_SETTINGS */
 555         gettext_noop("Write-Ahead Log / Settings"),
 556         /* WAL_CHECKPOINTS */
 557         gettext_noop("Write-Ahead Log / Checkpoints"),
 558         /* WAL_ARCHIVING */
 559         gettext_noop("Write-Ahead Log / Archiving"),
 560         /* REPLICATION */
 561         gettext_noop("Replication"),
 562         /* REPLICATION_SENDING */
 563         gettext_noop("Replication / Sending Servers"),
 564         /* REPLICATION_MASTER */
 565         gettext_noop("Replication / Master Server"),
 566         /* REPLICATION_STANDBY */
 567         gettext_noop("Replication / Standby Servers"),
 568         /* QUERY_TUNING */
 569         gettext_noop("Query Tuning"),
 570         /* QUERY_TUNING_METHOD */
 571         gettext_noop("Query Tuning / Planner Method Configuration"),
 572         /* QUERY_TUNING_COST */
 573         gettext_noop("Query Tuning / Planner Cost Constants"),
 574         /* QUERY_TUNING_GEQO */
 575         gettext_noop("Query Tuning / Genetic Query Optimizer"),
 576         /* QUERY_TUNING_OTHER */
 577         gettext_noop("Query Tuning / Other Planner Options"),
 578         /* LOGGING */
 579         gettext_noop("Reporting and Logging"),
 580         /* LOGGING_WHERE */
 581         gettext_noop("Reporting and Logging / Where to Log"),
 582         /* LOGGING_WHEN */
 583         gettext_noop("Reporting and Logging / When to Log"),
 584         /* LOGGING_WHAT */
 585         gettext_noop("Reporting and Logging / What to Log"),
 586         /* STATS */
 587         gettext_noop("Statistics"),
 588         /* STATS_MONITORING */
 589         gettext_noop("Statistics / Monitoring"),
 590         /* STATS_COLLECTOR */
 591         gettext_noop("Statistics / Query and Index Statistics Collector"),
 592         /* AUTOVACUUM */
 593         gettext_noop("Autovacuum"),
 594         /* CLIENT_CONN */
 595         gettext_noop("Client Connection Defaults"),
 596         /* CLIENT_CONN_STATEMENT */
 597         gettext_noop("Client Connection Defaults / Statement Behavior"),
 598         /* CLIENT_CONN_LOCALE */
 599         gettext_noop("Client Connection Defaults / Locale and Formatting"),
 600         /* CLIENT_CONN_OTHER */
 601         gettext_noop("Client Connection Defaults / Other Defaults"),
 602         /* LOCK_MANAGEMENT */
 603         gettext_noop("Lock Management"),
 604         /* COMPAT_OPTIONS */
 605         gettext_noop("Version and Platform Compatibility"),
 606         /* COMPAT_OPTIONS_PREVIOUS */
 607         gettext_noop("Version and Platform Compatibility / Previous PostgreSQL Versions"),
 608         /* COMPAT_OPTIONS_CLIENT */
 609         gettext_noop("Version and Platform Compatibility / Other Platforms and Clients"),
 610         /* ERROR_HANDLING */
 611         gettext_noop("Error Handling"),
 612         /* PRESET_OPTIONS */
 613         gettext_noop("Preset Options"),
 614         /* CUSTOM_OPTIONS */
 615         gettext_noop("Customized Options"),
 616         /* DEVELOPER_OPTIONS */
 617         gettext_noop("Developer Options"),
 618         /* help_config wants this array to be null-terminated */
 619         NULL
 620 };
 621
 622 /*
 623  * Displayable names for GUC variable types (enum config_type)
 624  *
 625  * Note: these strings are deliberately not localized.
 626  */
 627 const char *const config_type_names[] =
 628 {
 629          /* PGC_BOOL */ "bool",
 630          /* PGC_INT */ "integer",
 631          /* PGC_REAL */ "real",
 632          /* PGC_STRING */ "string",
 633          /* PGC_ENUM */ "enum"
 634 };
 635
 636
 637 /*
 638  * Contents of GUC tables
 639  *
 640  * See src/backend/utils/misc/README for design notes.
 641  *
 642  * TO ADD AN OPTION:
 643  *
 644  * 1. Declare a global variable of type bool, int, double, or char*
 645  *        and make use of it.
 646  *
 647  * 2. Decide at what times it's safe to set the option. See guc.h for
 648  *        details.
 649  *
 650  * 3. Decide on a name, a default value, upper and lower bounds (if
 651  *        applicable), etc.
 652  *
 653  * 4. Add a record below.
 654  *
 655  * 5. Add it to src/backend/utils/misc/postgresql.conf.sample, if
 656  *        appropriate.
 657  *
 658  * 6. Don't forget to document the option (at least in config.sgml).
 659  *
 660  * 7. If it's a new GUC_LIST option you must edit pg_dumpall.c to ensure
 661  *        it is not single quoted at dump time.
 662  */
 663
 664
 665 /******** option records follow ********/
 666
 667 static struct config_bool ConfigureNamesBool[] =
 668 {
 669         {
 670                 {"enable_seqscan", PGC_USERSET, QUERY_TUNING_METHOD,
 671                         gettext_noop("Enables the planner's use of sequential-scan plans."),
 672                         NULL
 673                 },
 674                 &enable_seqscan,
 675                 true,
 676                 NULL, NULL, NULL
 677         },
 678         {
 679                 {"enable_indexscan", PGC_USERSET, QUERY_TUNING_METHOD,
 680                         gettext_noop("Enables the planner's use of index-scan plans."),
 681                         NULL
 682                 },
 683                 &enable_indexscan,
 684                 true,
 685                 NULL, NULL, NULL
 686         },
 687         {
 688                 {"enable_indexonlyscan", PGC_USERSET, QUERY_TUNING_METHOD,
 689                         gettext_noop("Enables the planner's use of index-only-scan plans."),
 690                         NULL
 691                 },
 692                 &enable_indexonlyscan,
 693                 true,
 694                 NULL, NULL, NULL
 695         },
 696         {
 697                 {"enable_bitmapscan", PGC_USERSET, QUERY_TUNING_METHOD,
 698                         gettext_noop("Enables the planner's use of bitmap-scan plans."),
 699                         NULL
 700                 },
 701                 &enable_bitmapscan,
 702                 true,
 703                 NULL, NULL, NULL
 704         },
 705         {
 706                 {"enable_tidscan", PGC_USERSET, QUERY_TUNING_METHOD,
 707                         gettext_noop("Enables the planner's use of TID scan plans."),
 708                         NULL
 709                 },
 710                 &enable_tidscan,
 711                 true,
 712                 NULL, NULL, NULL
 713         },
 714         {
 715                 {"enable_sort", PGC_USERSET, QUERY_TUNING_METHOD,
 716                         gettext_noop("Enables the planner's use of explicit sort steps."),
 717                         NULL
 718                 },
 719                 &enable_sort,
 720                 true,
 721                 NULL, NULL, NULL
 722         },
 723         {
 724                 {"enable_hashagg", PGC_USERSET, QUERY_TUNING_METHOD,
 725                         gettext_noop("Enables the planner's use of hashed aggregation plans."),
 726                         NULL
 727                 },
 728                 &enable_hashagg,
 729                 true,
 730                 NULL, NULL, NULL
 731         },
 732         {
 733                 {"enable_material", PGC_USERSET, QUERY_TUNING_METHOD,
 734                         gettext_noop("Enables the planner's use of materialization."),
 735                         NULL
 736                 },
 737                 &enable_material,
 738                 true,
 739                 NULL, NULL, NULL
 740         },
 741         {
 742                 {"enable_nestloop", PGC_USERSET, QUERY_TUNING_METHOD,
 743                         gettext_noop("Enables the planner's use of nested-loop join plans."),
 744                         NULL
 745                 },
 746                 &enable_nestloop,
 747                 true,
 748                 NULL, NULL, NULL
 749         },
 750         {
 751                 {"enable_mergejoin", PGC_USERSET, QUERY_TUNING_METHOD,
 752                         gettext_noop("Enables the planner's use of merge join plans."),
 753                         NULL
 754                 },
 755                 &enable_mergejoin,
 756                 true,
 757                 NULL, NULL, NULL
 758         },
 759         {
 760                 {"enable_hashjoin", PGC_USERSET, QUERY_TUNING_METHOD,
 761                         gettext_noop("Enables the planner's use of hash join plans."),
 762                         NULL
 763                 },
 764                 &enable_hashjoin,
 765                 true,
 766                 NULL, NULL, NULL
 767         },
 768         {
 769                 {"geqo", PGC_USERSET, QUERY_TUNING_GEQO,
 770                         gettext_noop("Enables genetic query optimization."),
 771                         gettext_noop("This algorithm attempts to do planning without "
 772                                                  "exhaustive searching.")
 773                 },
 774                 &enable_geqo,
 775                 true,
 776                 NULL, NULL, NULL
 777         },
 778         {
 779                 /* Not for general use --- used by SET SESSION AUTHORIZATION */
 780                 {"is_superuser", PGC_INTERNAL, UNGROUPED,
 781                         gettext_noop("Shows whether the current user is a superuser."),
 782                         NULL,
 783                         GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
 784                 },
 785                 &session_auth_is_superuser,
 786                 false,
 787                 NULL, NULL, NULL
 788         },
 789         {
 790                 {"bonjour", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
 791                         gettext_noop("Enables advertising the server via Bonjour."),
 792                         NULL
 793                 },
 794                 &enable_bonjour,
 795                 false,
 796                 check_bonjour, NULL, NULL
 797         },
 798         {
 799                 {"ssl", PGC_POSTMASTER, CONN_AUTH_SECURITY,
 800                         gettext_noop("Enables SSL connections."),
 801                         NULL
 802                 },
 803                 &EnableSSL,
 804                 false,
 805                 check_ssl, NULL, NULL
 806         },
 807         {
 808                 {"fsync", PGC_SIGHUP, WAL_SETTINGS,
 809                         gettext_noop("Forces synchronization of updates to disk."),
 810                         gettext_noop("The server will use the fsync() system call in several places to make "
 811                         "sure that updates are physically written to disk. This insures "
 812                                                  "that a database cluster will recover to a consistent state after "
 813                                                  "an operating system or hardware crash.")
 814                 },
 815                 &enableFsync,
 816                 true,
 817                 NULL, NULL, NULL
 818         },
 819         {
 820                 {"zero_damaged_pages", PGC_SUSET, DEVELOPER_OPTIONS,
 821                         gettext_noop("Continues processing past damaged page headers."),
 822                         gettext_noop("Detection of a damaged page header normally causes PostgreSQL to "
 823                                 "report an error, aborting the current transaction. Setting "
 824                                                  "zero_damaged_pages to true causes the system to instead report a "
 825                                                  "warning, zero out the damaged page, and continue processing. This "
 826                                                  "behavior will destroy data, namely all the rows on the damaged page."),
 827                         GUC_NOT_IN_SAMPLE
 828                 },
 829                 &zero_damaged_pages,
 830                 false,
 831                 NULL, NULL, NULL
 832         },
 833         {
 834                 {"full_page_writes", PGC_SIGHUP, WAL_SETTINGS,
 835                         gettext_noop("Writes full pages to WAL when first modified after a checkpoint."),
 836                         gettext_noop("A page write in process during an operating system crash might be "
 837                                                  "only partially written to disk.  During recovery, the row changes "
 838                           "stored in WAL are not enough to recover.  This option writes "
 839                                                  "pages when first modified after a checkpoint to WAL so full recovery "
 840                                                  "is possible.")
 841                 },
 842                 &fullPageWrites,
 843                 true,
 844                 NULL, NULL, NULL
 845         },
 846         {
 847                 {"log_checkpoints", PGC_SIGHUP, LOGGING_WHAT,
 848                         gettext_noop("Logs each checkpoint."),
 849                         NULL
 850                 },
 851                 &log_checkpoints,
 852                 false,
 853                 NULL, NULL, NULL
 854         },
 855         {
 856                 {"log_connections", PGC_BACKEND, LOGGING_WHAT,
 857                         gettext_noop("Logs each successful connection."),
 858                         NULL
 859                 },
 860                 &Log_connections,
 861                 false,
 862                 NULL, NULL, NULL
 863         },
 864         {
 865                 {"log_disconnections", PGC_BACKEND, LOGGING_WHAT,
 866                         gettext_noop("Logs end of a session, including duration."),
 867                         NULL
 868                 },
 869                 &Log_disconnections,
 870                 false,
 871                 NULL, NULL, NULL
 872         },
 873         {
 874                 {"debug_assertions", PGC_USERSET, DEVELOPER_OPTIONS,
 875                         gettext_noop("Turns on various assertion checks."),
 876                         gettext_noop("This is a debugging aid."),
 877                         GUC_NOT_IN_SAMPLE
 878                 },
 879                 &assert_enabled,
 880 #ifdef USE_ASSERT_CHECKING
 881                 true,
 882 #else
 883                 false,
 884 #endif
 885                 check_debug_assertions, NULL, NULL
 886         },
 887
 888         {
 889                 {"exit_on_error", PGC_USERSET, ERROR_HANDLING_OPTIONS,
 890                         gettext_noop("Terminate session on any error."),
 891                         NULL
 892                 },
 893                 &ExitOnAnyError,
 894                 false,
 895                 NULL, NULL, NULL
 896         },
 897         {
 898                 {"restart_after_crash", PGC_SIGHUP, ERROR_HANDLING_OPTIONS,
 899                         gettext_noop("Reinitialize server after backend crash."),
 900                         NULL
 901                 },
 902                 &restart_after_crash,
 903                 true,
 904                 NULL, NULL, NULL
 905         },
 906
 907         {
 908                 {"log_duration", PGC_SUSET, LOGGING_WHAT,
 909                         gettext_noop("Logs the duration of each completed SQL statement."),
 910                         NULL
 911                 },
 912                 &log_duration,
 913                 false,
 914                 NULL, NULL, NULL
 915         },
 916         {
 917                 {"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 918                         gettext_noop("Logs each query's parse tree."),
 919                         NULL
 920                 },
 921                 &Debug_print_parse,
 922                 false,
 923                 NULL, NULL, NULL
 924         },
 925         {
 926                 {"debug_print_rewritten", PGC_USERSET, LOGGING_WHAT,
 927                         gettext_noop("Logs each query's rewritten parse tree."),
 928                         NULL
 929                 },
 930                 &Debug_print_rewritten,
 931                 false,
 932                 NULL, NULL, NULL
 933         },
 934         {
 935                 {"debug_print_plan", PGC_USERSET, LOGGING_WHAT,
 936                         gettext_noop("Logs each query's execution plan."),
 937                         NULL
 938                 },
 939                 &Debug_print_plan,
 940                 false,
 941                 NULL, NULL, NULL
 942         },
 943         {
 944                 {"debug_pretty_print", PGC_USERSET, LOGGING_WHAT,
 945                         gettext_noop("Indents parse and plan tree displays."),
 946                         NULL
 947                 },
 948                 &Debug_pretty_print,
 949                 true,
 950                 NULL, NULL, NULL
 951         },
 952         {
 953                 {"log_parser_stats", PGC_SUSET, STATS_MONITORING,
 954                         gettext_noop("Writes parser performance statistics to the server log."),
 955                         NULL
 956                 },
 957                 &log_parser_stats,
 958                 false,
 959                 check_stage_log_stats, NULL, NULL
 960         },
 961         {
 962                 {"log_planner_stats", PGC_SUSET, STATS_MONITORING,
 963                         gettext_noop("Writes planner performance statistics to the server log."),
 964                         NULL
 965                 },
 966                 &log_planner_stats,
 967                 false,
 968                 check_stage_log_stats, NULL, NULL
 969         },
 970         {
 971                 {"log_executor_stats", PGC_SUSET, STATS_MONITORING,
 972                         gettext_noop("Writes executor performance statistics to the server log."),
 973                         NULL
 974                 },
 975                 &log_executor_stats,
 976                 false,
 977                 check_stage_log_stats, NULL, NULL
 978         },
 979         {
 980                 {"log_statement_stats", PGC_SUSET, STATS_MONITORING,
 981                         gettext_noop("Writes cumulative performance statistics to the server log."),
 982                         NULL
 983                 },
 984                 &log_statement_stats,
 985                 false,
 986                 check_log_stats, NULL, NULL
 987         },
 988 #ifdef BTREE_BUILD_STATS
 989         {
 990                 {"log_btree_build_stats", PGC_SUSET, DEVELOPER_OPTIONS,
 991                         gettext_noop("No description available."),
 992                         NULL,
 993                         GUC_NOT_IN_SAMPLE
 994                 },
 995                 &log_btree_build_stats,
 996                 false,
 997                 NULL, NULL, NULL
 998         },
 999 #endif
1000
1001         {
1002                 {"track_activities", PGC_SUSET, STATS_COLLECTOR,
1003                         gettext_noop("Collects information about executing commands."),
1004                         gettext_noop("Enables the collection of information on the currently "
1005                                                  "executing command of each session, along with "
1006                                                  "the time at which that command began execution.")
1007                 },
1008                 &pgstat_track_activities,
1009                 true,
1010                 NULL, NULL, NULL
1011         },
1012         {
1013                 {"track_counts", PGC_SUSET, STATS_COLLECTOR,
1014                         gettext_noop("Collects statistics on database activity."),
1015                         NULL
1016                 },
1017                 &pgstat_track_counts,
1018                 true,
1019                 NULL, NULL, NULL
1020         },
1021
1022         {
1023                 {"update_process_title", PGC_SUSET, STATS_COLLECTOR,
1024                         gettext_noop("Updates the process title to show the active SQL command."),
1025                         gettext_noop("Enables updating of the process title every time a new SQL command is received by the server.")
1026                 },
1027                 &update_process_title,
1028                 true,
1029                 NULL, NULL, NULL
1030         },
1031
1032         {
1033                 {"autovacuum", PGC_SIGHUP, AUTOVACUUM,
1034                         gettext_noop("Starts the autovacuum subprocess."),
1035                         NULL
1036                 },
1037                 &autovacuum_start_daemon,
1038                 true,
1039                 NULL, NULL, NULL
1040         },
1041
1042         {
1043                 {"trace_notify", PGC_USERSET, DEVELOPER_OPTIONS,
1044                         gettext_noop("Generates debugging output for LISTEN and NOTIFY."),
1045                         NULL,
1046                         GUC_NOT_IN_SAMPLE
1047                 },
1048                 &Trace_notify,
1049                 false,
1050                 NULL, NULL, NULL
1051         },
1052
1053 #ifdef LOCK_DEBUG
1054         {
1055                 {"trace_locks", PGC_SUSET, DEVELOPER_OPTIONS,
1056                         gettext_noop("No description available."),
1057                         NULL,
1058                         GUC_NOT_IN_SAMPLE
1059                 },
1060                 &Trace_locks,
1061                 false,
1062                 NULL, NULL, NULL
1063         },
1064         {
1065                 {"trace_userlocks", PGC_SUSET, DEVELOPER_OPTIONS,
1066                         gettext_noop("No description available."),
1067                         NULL,
1068                         GUC_NOT_IN_SAMPLE
1069                 },
1070                 &Trace_userlocks,
1071                 false,
1072                 NULL, NULL, NULL
1073         },
1074         {
1075                 {"trace_lwlocks", PGC_SUSET, DEVELOPER_OPTIONS,
1076                         gettext_noop("No description available."),
1077                         NULL,
1078                         GUC_NOT_IN_SAMPLE
1079                 },
1080                 &Trace_lwlocks,
1081                 false,
1082                 NULL, NULL, NULL
1083         },
1084         {
1085                 {"debug_deadlocks", PGC_SUSET, DEVELOPER_OPTIONS,
1086                         gettext_noop("No description available."),
1087                         NULL,
1088                         GUC_NOT_IN_SAMPLE
1089                 },
1090                 &Debug_deadlocks,
1091                 false,
1092                 NULL, NULL, NULL
1093         },
1094 #endif
1095
1096         {
1097                 {"log_lock_waits", PGC_SUSET, LOGGING_WHAT,
1098                         gettext_noop("Logs long lock waits."),
1099                         NULL
1100                 },
1101                 &log_lock_waits,
1102                 false,
1103                 NULL, NULL, NULL
1104         },
1105
1106         {
1107                 {"log_hostname", PGC_SIGHUP, LOGGING_WHAT,
1108                         gettext_noop("Logs the host name in the connection logs."),
1109                         gettext_noop("By default, connection logs only show the IP address "
1110                                                  "of the connecting host. If you want them to show the host name you "
1111                           "can turn this on, but depending on your host name resolution "
1112                            "setup it might impose a non-negligible performance penalty.")
1113                 },
1114                 &log_hostname,
1115                 false,
1116                 NULL, NULL, NULL
1117         },
1118         {
1119                 {"sql_inheritance", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1120                         gettext_noop("Causes subtables to be included by default in various commands."),
1121                         NULL
1122                 },
1123                 &SQL_inheritance,
1124                 true,
1125                 NULL, NULL, NULL
1126         },
1127         {
1128                 {"password_encryption", PGC_USERSET, CONN_AUTH_SECURITY,
1129                         gettext_noop("Encrypt passwords."),
1130                         gettext_noop("When a password is specified in CREATE USER or "
1131                            "ALTER USER without writing either ENCRYPTED or UNENCRYPTED, "
1132                                                  "this parameter determines whether the password is to be encrypted.")
1133                 },
1134                 &Password_encryption,
1135                 true,
1136                 NULL, NULL, NULL
1137         },
1138         {
1139                 {"transform_null_equals", PGC_USERSET, COMPAT_OPTIONS_CLIENT,
1140                         gettext_noop("Treats \"expr=NULL\" as \"expr IS NULL\"."),
1141                         gettext_noop("When turned on, expressions of the form expr = NULL "
1142                            "(or NULL = expr) are treated as expr IS NULL, that is, they "
1143                                 "return true if expr evaluates to the null value, and false "
1144                            "otherwise. The correct behavior of expr = NULL is to always "
1145                                                  "return null (unknown).")
1146                 },
1147                 &Transform_null_equals,
1148                 false,
1149                 NULL, NULL, NULL
1150         },
1151         {
1152                 {"db_user_namespace", PGC_SIGHUP, CONN_AUTH_SECURITY,
1153                         gettext_noop("Enables per-database user names."),
1154                         NULL
1155                 },
1156                 &Db_user_namespace,
1157                 false,
1158                 NULL, NULL, NULL
1159         },
1160         {
1161                 /* only here for backwards compatibility */
1162                 {"autocommit", PGC_USERSET, CLIENT_CONN_STATEMENT,
1163                         gettext_noop("This parameter doesn't do anything."),
1164                         gettext_noop("It's just here so that we won't choke on SET AUTOCOMMIT TO ON from 7.3-vintage clients."),
1165                         GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE
1166                 },
1167                 &phony_autocommit,
1168                 true,
1169                 check_phony_autocommit, NULL, NULL
1170         },
1171         {
1172                 {"default_transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT,
1173                         gettext_noop("Sets the default read-only status of new transactions."),
1174                         NULL
1175                 },
1176                 &DefaultXactReadOnly,
1177                 false,
1178                 NULL, NULL, NULL
1179         },
1180         {
1181                 {"transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT,
1182                         gettext_noop("Sets the current transaction's read-only status."),
1183                         NULL,
1184                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1185                 },
1186                 &XactReadOnly,
1187                 false,
1188                 check_transaction_read_only, NULL, NULL
1189         },
1190         {
1191                 {"default_transaction_deferrable", PGC_USERSET, CLIENT_CONN_STATEMENT,
1192                         gettext_noop("Sets the default deferrable status of new transactions."),
1193                         NULL
1194                 },
1195                 &DefaultXactDeferrable,
1196                 false,
1197                 NULL, NULL, NULL
1198         },
1199         {
1200                 {"transaction_deferrable", PGC_USERSET, CLIENT_CONN_STATEMENT,
1201                         gettext_noop("Whether to defer a read-only serializable transaction until it can be executed with no possible serialization failures."),
1202                         NULL,
1203                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1204                 },
1205                 &XactDeferrable,
1206                 false,
1207                 check_transaction_deferrable, NULL, NULL
1208         },
1209         {
1210                 {"check_function_bodies", PGC_USERSET, CLIENT_CONN_STATEMENT,
1211                         gettext_noop("Check function bodies during CREATE FUNCTION."),
1212                         NULL
1213                 },
1214                 &check_function_bodies,
1215                 true,
1216                 NULL, NULL, NULL
1217         },
1218         {
1219                 {"array_nulls", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1220                         gettext_noop("Enable input of NULL elements in arrays."),
1221                         gettext_noop("When turned on, unquoted NULL in an array input "
1222                                                  "value means a null value; "
1223                                                  "otherwise it is taken literally.")
1224                 },
1225                 &Array_nulls,
1226                 true,
1227                 NULL, NULL, NULL
1228         },
1229         {
1230                 {"default_with_oids", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1231                         gettext_noop("Create new tables with OIDs by default."),
1232                         NULL
1233                 },
1234                 &default_with_oids,
1235                 false,
1236                 NULL, NULL, NULL
1237         },
1238         {
1239                 {"logging_collector", PGC_POSTMASTER, LOGGING_WHERE,
1240                         gettext_noop("Start a subprocess to capture stderr output and/or csvlogs into log files."),
1241                         NULL
1242                 },
1243                 &Logging_collector,
1244                 false,
1245                 NULL, NULL, NULL
1246         },
1247         {
1248                 {"log_truncate_on_rotation", PGC_SIGHUP, LOGGING_WHERE,
1249                         gettext_noop("Truncate existing log files of same name during log rotation."),
1250                         NULL
1251                 },
1252                 &Log_truncate_on_rotation,
1253                 false,
1254                 NULL, NULL, NULL
1255         },
1256
1257 #ifdef TRACE_SORT
1258         {
1259                 {"trace_sort", PGC_USERSET, DEVELOPER_OPTIONS,
1260                         gettext_noop("Emit information about resource usage in sorting."),
1261                         NULL,
1262                         GUC_NOT_IN_SAMPLE
1263                 },
1264                 &trace_sort,
1265                 false,
1266                 NULL, NULL, NULL
1267         },
1268 #endif
1269
1270 #ifdef TRACE_SYNCSCAN
1271         /* this is undocumented because not exposed in a standard build */
1272         {
1273                 {"trace_syncscan", PGC_USERSET, DEVELOPER_OPTIONS,
1274                         gettext_noop("Generate debugging output for synchronized scanning."),
1275                         NULL,
1276                         GUC_NOT_IN_SAMPLE
1277                 },
1278                 &trace_syncscan,
1279                 false,
1280                 NULL, NULL, NULL
1281         },
1282 #endif
1283
1284 #ifdef DEBUG_BOUNDED_SORT
1285         /* this is undocumented because not exposed in a standard build */
1286         {
1287                 {
1288                         "optimize_bounded_sort", PGC_USERSET, QUERY_TUNING_METHOD,
1289                         gettext_noop("Enable bounded sorting using heap sort."),
1290                         NULL,
1291                         GUC_NOT_IN_SAMPLE
1292                 },
1293                 &optimize_bounded_sort,
1294                 true,
1295                 NULL, NULL, NULL
1296         },
1297 #endif
1298
1299 #ifdef WAL_DEBUG
1300         {
1301                 {"wal_debug", PGC_SUSET, DEVELOPER_OPTIONS,
1302                         gettext_noop("Emit WAL-related debugging output."),
1303                         NULL,
1304                         GUC_NOT_IN_SAMPLE
1305                 },
1306                 &XLOG_DEBUG,
1307                 false,
1308                 NULL, NULL, NULL
1309         },
1310 #endif
1311
1312         {
1313                 {"integer_datetimes", PGC_INTERNAL, PRESET_OPTIONS,
1314                         gettext_noop("Datetimes are integer based."),
1315                         NULL,
1316                         GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1317                 },
1318                 &integer_datetimes,
1319 #ifdef HAVE_INT64_TIMESTAMP
1320                 true,
1321 #else
1322                 false,
1323 #endif
1324                 NULL, NULL, NULL
1325         },
1326
1327         {
1328                 {"krb_caseins_users", PGC_SIGHUP, CONN_AUTH_SECURITY,
1329                         gettext_noop("Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive."),
1330                         NULL
1331                 },
1332                 &pg_krb_caseins_users,
1333                 false,
1334                 NULL, NULL, NULL
1335         },
1336
1337         {
1338                 {"escape_string_warning", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1339                         gettext_noop("Warn about backslash escapes in ordinary string literals."),
1340                         NULL
1341                 },
1342                 &escape_string_warning,
1343                 true,
1344                 NULL, NULL, NULL
1345         },
1346
1347         {
1348                 {"standard_conforming_strings", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1349                         gettext_noop("Causes '...' strings to treat backslashes literally."),
1350                         NULL,
1351                         GUC_REPORT
1352                 },
1353                 &standard_conforming_strings,
1354                 true,
1355                 NULL, NULL, NULL
1356         },
1357
1358         {
1359                 {"synchronize_seqscans", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1360                         gettext_noop("Enable synchronized sequential scans."),
1361                         NULL
1362                 },
1363                 &synchronize_seqscans,
1364                 true,
1365                 NULL, NULL, NULL
1366         },
1367
1368         {
1369                 {"archive_mode", PGC_POSTMASTER, WAL_ARCHIVING,
1370                         gettext_noop("Allows archiving of WAL files using archive_command."),
1371                         NULL
1372                 },
1373                 &XLogArchiveMode,
1374                 false,
1375                 NULL, NULL, NULL
1376         },
1377
1378         {
1379                 {"hot_standby", PGC_POSTMASTER, REPLICATION_STANDBY,
1380                         gettext_noop("Allows connections and queries during recovery."),
1381                         NULL
1382                 },
1383                 &EnableHotStandby,
1384                 false,
1385                 NULL, NULL, NULL
1386         },
1387
1388         {
1389                 {"hot_standby_feedback", PGC_SIGHUP, REPLICATION_STANDBY,
1390                         gettext_noop("Allows feedback from a hot standby to the primary that will avoid query conflicts."),
1391                         NULL
1392                 },
1393                 &hot_standby_feedback,
1394                 false,
1395                 NULL, NULL, NULL
1396         },
1397
1398         {
1399                 {"allow_system_table_mods", PGC_POSTMASTER, DEVELOPER_OPTIONS,
1400                         gettext_noop("Allows modifications of the structure of system tables."),
1401                         NULL,
1402                         GUC_NOT_IN_SAMPLE
1403                 },
1404                 &allowSystemTableMods,
1405                 false,
1406                 NULL, NULL, NULL
1407         },
1408
1409         {
1410                 {"ignore_system_indexes", PGC_BACKEND, DEVELOPER_OPTIONS,
1411                         gettext_noop("Disables reading from system indexes."),
1412                         gettext_noop("It does not prevent updating the indexes, so it is safe "
1413                                                  "to use.  The worst consequence is slowness."),
1414                         GUC_NOT_IN_SAMPLE
1415                 },
1416                 &IgnoreSystemIndexes,
1417                 false,
1418                 NULL, NULL, NULL
1419         },
1420
1421         {
1422                 {"lo_compat_privileges", PGC_SUSET, COMPAT_OPTIONS_PREVIOUS,
1423                         gettext_noop("Enables backward compatibility mode for privilege checks on large objects."),
1424                         gettext_noop("Skips privilege checks when reading or modifying large objects, "
1425                                   "for compatibility with PostgreSQL releases prior to 9.0.")
1426                 },
1427                 &lo_compat_privileges,
1428                 false,
1429                 NULL, NULL, NULL
1430         },
1431
1432         {
1433                 {"quote_all_identifiers", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1434                         gettext_noop("When generating SQL fragments, quote all identifiers."),
1435                         NULL,
1436                 },
1437                 &quote_all_identifiers,
1438                 false,
1439                 NULL, NULL, NULL
1440         },
1441
1442         /* End-of-list marker */
1443         {
1444                 {NULL, 0, 0, NULL, NULL}, NULL, false, NULL, NULL, NULL
1445         }
1446 };
1447
1448
1449 static struct config_int ConfigureNamesInt[] =
1450 {
1451         {
1452                 {"archive_timeout", PGC_SIGHUP, WAL_ARCHIVING,
1453                         gettext_noop("Forces a switch to the next xlog file if a "
1454                                                  "new file has not been started within N seconds."),
1455                         NULL,
1456                         GUC_UNIT_S
1457                 },
1458                 &XLogArchiveTimeout,
1459                 0, 0, INT_MAX,
1460                 NULL, NULL, NULL
1461         },
1462         {
1463                 {"post_auth_delay", PGC_BACKEND, DEVELOPER_OPTIONS,
1464                         gettext_noop("Waits N seconds on connection startup after authentication."),
1465                         gettext_noop("This allows attaching a debugger to the process."),
1466                         GUC_NOT_IN_SAMPLE | GUC_UNIT_S
1467                 },
1468                 &PostAuthDelay,
1469                 0, 0, INT_MAX,
1470                 NULL, NULL, NULL
1471         },
1472         {
1473                 {"default_statistics_target", PGC_USERSET, QUERY_TUNING_OTHER,
1474                         gettext_noop("Sets the default statistics target."),
1475                         gettext_noop("This applies to table columns that have not had a "
1476                                 "column-specific target set via ALTER TABLE SET STATISTICS.")
1477                 },
1478                 &default_statistics_target,
1479                 100, 1, 10000,
1480                 NULL, NULL, NULL
1481         },
1482         {
1483                 {"from_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
1484                         gettext_noop("Sets the FROM-list size beyond which subqueries "
1485                                                  "are not collapsed."),
1486                         gettext_noop("The planner will merge subqueries into upper "
1487                                 "queries if the resulting FROM list would have no more than "
1488                                                  "this many items.")
1489                 },
1490                 &from_collapse_limit,
1491                 8, 1, INT_MAX,
1492                 NULL, NULL, NULL
1493         },
1494         {
1495                 {"join_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
1496                         gettext_noop("Sets the FROM-list size beyond which JOIN "
1497                                                  "constructs are not flattened."),
1498                         gettext_noop("The planner will flatten explicit JOIN "
1499                                                  "constructs into lists of FROM items whenever a "
1500                                                  "list of no more than this many items would result.")
1501                 },
1502                 &join_collapse_limit,
1503                 8, 1, INT_MAX,
1504                 NULL, NULL, NULL
1505         },
1506         {
1507                 {"geqo_threshold", PGC_USERSET, QUERY_TUNING_GEQO,
1508                         gettext_noop("Sets the threshold of FROM items beyond which GEQO is used."),
1509                         NULL
1510                 },
1511                 &geqo_threshold,
1512                 12, 2, INT_MAX,
1513                 NULL, NULL, NULL
1514         },
1515         {
1516                 {"geqo_effort", PGC_USERSET, QUERY_TUNING_GEQO,
1517                         gettext_noop("GEQO: effort is used to set the default for other GEQO parameters."),
1518                         NULL
1519                 },
1520                 &Geqo_effort,
1521                 DEFAULT_GEQO_EFFORT, MIN_GEQO_EFFORT, MAX_GEQO_EFFORT,
1522                 NULL, NULL, NULL
1523         },
1524         {
1525                 {"geqo_pool_size", PGC_USERSET, QUERY_TUNING_GEQO,
1526                         gettext_noop("GEQO: number of individuals in the population."),
1527                         gettext_noop("Zero selects a suitable default value.")
1528                 },
1529                 &Geqo_pool_size,
1530                 0, 0, INT_MAX,
1531                 NULL, NULL, NULL
1532         },
1533         {
1534                 {"geqo_generations", PGC_USERSET, QUERY_TUNING_GEQO,
1535                         gettext_noop("GEQO: number of iterations of the algorithm."),
1536                         gettext_noop("Zero selects a suitable default value.")
1537                 },
1538                 &Geqo_generations,
1539                 0, 0, INT_MAX,
1540                 NULL, NULL, NULL
1541         },
1542
1543         {
1544                 /* This is PGC_SUSET to prevent hiding from log_lock_waits. */
1545                 {"deadlock_timeout", PGC_SUSET, LOCK_MANAGEMENT,
1546                         gettext_noop("Sets the time to wait on a lock before checking for deadlock."),
1547                         NULL,
1548                         GUC_UNIT_MS
1549                 },
1550                 &DeadlockTimeout,
1551                 1000, 1, INT_MAX,
1552                 NULL, NULL, NULL
1553         },
1554
1555         {
1556                 {"max_standby_archive_delay", PGC_SIGHUP, REPLICATION_STANDBY,
1557                         gettext_noop("Sets the maximum delay before canceling queries when a hot standby server is processing archived WAL data."),
1558                         NULL,
1559                         GUC_UNIT_MS
1560                 },
1561                 &max_standby_archive_delay,
1562                 30 * 1000, -1, INT_MAX,
1563                 NULL, NULL, NULL
1564         },
1565
1566         {
1567                 {"max_standby_streaming_delay", PGC_SIGHUP, REPLICATION_STANDBY,
1568                         gettext_noop("Sets the maximum delay before canceling queries when a hot standby server is processing streamed WAL data."),
1569                         NULL,
1570                         GUC_UNIT_MS
1571                 },
1572                 &max_standby_streaming_delay,
1573                 30 * 1000, -1, INT_MAX,
1574                 NULL, NULL, NULL
1575         },
1576
1577         {
1578                 {"wal_receiver_status_interval", PGC_SIGHUP, REPLICATION_STANDBY,
1579                         gettext_noop("Sets the maximum interval between WAL receiver status reports to the primary."),
1580                         NULL,
1581                         GUC_UNIT_S
1582                 },
1583                 &wal_receiver_status_interval,
1584                 10, 0, INT_MAX / 1000,
1585                 NULL, NULL, NULL
1586         },
1587
1588         {
1589                 {"max_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1590                         gettext_noop("Sets the maximum number of concurrent connections."),
1591                         NULL
1592                 },
1593                 &MaxConnections,
1594                 100, 1, MAX_BACKENDS,
1595                 check_maxconnections, assign_maxconnections, NULL
1596         },
1597
1598         {
1599                 {"superuser_reserved_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1600                         gettext_noop("Sets the number of connection slots reserved for superusers."),
1601                         NULL
1602                 },
1603                 &ReservedBackends,
1604                 3, 0, MAX_BACKENDS,
1605                 NULL, NULL, NULL
1606         },
1607
1608         /*
1609          * We sometimes multiply the number of shared buffers by two without
1610          * checking for overflow, so we mustn't allow more than INT_MAX / 2.
1611          */
1612         {
1613                 {"shared_buffers", PGC_POSTMASTER, RESOURCES_MEM,
1614                         gettext_noop("Sets the number of shared memory buffers used by the server."),
1615                         NULL,
1616                         GUC_UNIT_BLOCKS
1617                 },
1618                 &NBuffers,
1619                 1024, 16, INT_MAX / 2,
1620                 NULL, NULL, NULL
1621         },
1622
1623         {
1624                 {"temp_buffers", PGC_USERSET, RESOURCES_MEM,
1625                         gettext_noop("Sets the maximum number of temporary buffers used by each session."),
1626                         NULL,
1627                         GUC_UNIT_BLOCKS
1628                 },
1629                 &num_temp_buffers,
1630                 1024, 100, INT_MAX / 2,
1631                 check_temp_buffers, NULL, NULL
1632         },
1633
1634         {
1635                 {"port", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1636                         gettext_noop("Sets the TCP port the server listens on."),
1637                         NULL
1638                 },
1639                 &PostPortNumber,
1640                 DEF_PGPORT, 1, 65535,
1641                 NULL, NULL, NULL
1642         },
1643
1644         {
1645                 {"unix_socket_permissions", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1646                         gettext_noop("Sets the access permissions of the Unix-domain socket."),
1647                         gettext_noop("Unix-domain sockets use the usual Unix file system "
1648                                                  "permission set. The parameter value is expected "
1649                                                  "to be a numeric mode specification in the form "
1650                                                  "accepted by the chmod and umask system calls. "
1651                                                  "(To use the customary octal format the number must "
1652                                                  "start with a 0 (zero).)")
1653                 },
1654                 &Unix_socket_permissions,
1655                 0777, 0000, 0777,
1656                 NULL, NULL, show_unix_socket_permissions
1657         },
1658
1659         {
1660                 {"log_file_mode", PGC_SIGHUP, LOGGING_WHERE,
1661                         gettext_noop("Sets the file permissions for log files."),
1662                         gettext_noop("The parameter value is expected "
1663                                                  "to be a numeric mode specification in the form "
1664                                                  "accepted by the chmod and umask system calls. "
1665                                                  "(To use the customary octal format the number must "
1666                                                  "start with a 0 (zero).)")
1667                 },
1668                 &Log_file_mode,
1669                 0600, 0000, 0777,
1670                 NULL, NULL, show_log_file_mode
1671         },
1672
1673         {
1674                 {"work_mem", PGC_USERSET, RESOURCES_MEM,
1675                         gettext_noop("Sets the maximum memory to be used for query workspaces."),
1676                         gettext_noop("This much memory can be used by each internal "
1677                                                  "sort operation and hash table before switching to "
1678                                                  "temporary disk files."),
1679                         GUC_UNIT_KB
1680                 },
1681                 &work_mem,
1682                 1024, 64, MAX_KILOBYTES,
1683                 NULL, NULL, NULL
1684         },
1685
1686         {
1687                 {"maintenance_work_mem", PGC_USERSET, RESOURCES_MEM,
1688                         gettext_noop("Sets the maximum memory to be used for maintenance operations."),
1689                         gettext_noop("This includes operations such as VACUUM and CREATE INDEX."),
1690                         GUC_UNIT_KB
1691                 },
1692                 &maintenance_work_mem,
1693                 16384, 1024, MAX_KILOBYTES,
1694                 NULL, NULL, NULL
1695         },
1696
1697         /*
1698          * We use the hopefully-safely-small value of 100kB as the compiled-in
1699          * default for max_stack_depth.  InitializeGUCOptions will increase it if
1700          * possible, depending on the actual platform-specific stack limit.
1701          */
1702         {
1703                 {"max_stack_depth", PGC_SUSET, RESOURCES_MEM,
1704                         gettext_noop("Sets the maximum stack depth, in kilobytes."),
1705                         NULL,
1706                         GUC_UNIT_KB
1707                 },
1708                 &max_stack_depth,
1709                 100, 100, MAX_KILOBYTES,
1710                 check_max_stack_depth, assign_max_stack_depth, NULL
1711         },
1712
1713         {
1714                 {"temp_file_limit", PGC_SUSET, RESOURCES_DISK,
1715                         gettext_noop("Limits the total size of all temp files used by each session."),
1716                         gettext_noop("-1 means no limit."),
1717                         GUC_UNIT_KB
1718                 },
1719                 &temp_file_limit,
1720                 -1, -1, INT_MAX,
1721                 NULL, NULL, NULL
1722         },
1723
1724         {
1725                 {"vacuum_cost_page_hit", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1726                         gettext_noop("Vacuum cost for a page found in the buffer cache."),
1727                         NULL
1728                 },
1729                 &VacuumCostPageHit,
1730                 1, 0, 10000,
1731                 NULL, NULL, NULL
1732         },
1733
1734         {
1735                 {"vacuum_cost_page_miss", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1736                         gettext_noop("Vacuum cost for a page not found in the buffer cache."),
1737                         NULL
1738                 },
1739                 &VacuumCostPageMiss,
1740                 10, 0, 10000,
1741                 NULL, NULL, NULL
1742         },
1743
1744         {
1745                 {"vacuum_cost_page_dirty", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1746                         gettext_noop("Vacuum cost for a page dirtied by vacuum."),
1747                         NULL
1748                 },
1749                 &VacuumCostPageDirty,
1750                 20, 0, 10000,
1751                 NULL, NULL, NULL
1752         },
1753
1754         {
1755                 {"vacuum_cost_limit", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1756                         gettext_noop("Vacuum cost amount available before napping."),
1757                         NULL
1758                 },
1759                 &VacuumCostLimit,
1760                 200, 1, 10000,
1761                 NULL, NULL, NULL
1762         },
1763
1764         {
1765                 {"vacuum_cost_delay", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1766                         gettext_noop("Vacuum cost delay in milliseconds."),
1767                         NULL,
1768                         GUC_UNIT_MS
1769                 },
1770                 &VacuumCostDelay,
1771                 0, 0, 100,
1772                 NULL, NULL, NULL
1773         },
1774
1775         {
1776                 {"autovacuum_vacuum_cost_delay", PGC_SIGHUP, AUTOVACUUM,
1777                         gettext_noop("Vacuum cost delay in milliseconds, for autovacuum."),
1778                         NULL,
1779                         GUC_UNIT_MS
1780                 },
1781                 &autovacuum_vac_cost_delay,
1782                 20, -1, 100,
1783                 NULL, NULL, NULL
1784         },
1785
1786         {
1787                 {"autovacuum_vacuum_cost_limit", PGC_SIGHUP, AUTOVACUUM,
1788                         gettext_noop("Vacuum cost amount available before napping, for autovacuum."),
1789                         NULL
1790                 },
1791                 &autovacuum_vac_cost_limit,
1792                 -1, -1, 10000,
1793                 NULL, NULL, NULL
1794         },
1795
1796         {
1797                 {"max_files_per_process", PGC_POSTMASTER, RESOURCES_KERNEL,
1798                         gettext_noop("Sets the maximum number of simultaneously open files for each server process."),
1799                         NULL
1800                 },
1801                 &max_files_per_process,
1802                 1000, 25, INT_MAX,
1803                 NULL, NULL, NULL
1804         },
1805
1806         /*
1807          * See also CheckRequiredParameterValues() if this parameter changes
1808          */
1809         {
1810                 {"max_prepared_transactions", PGC_POSTMASTER, RESOURCES_MEM,
1811                         gettext_noop("Sets the maximum number of simultaneously prepared transactions."),
1812                         NULL
1813                 },
1814                 &max_prepared_xacts,
1815                 0, 0, MAX_BACKENDS,
1816                 NULL, NULL, NULL
1817         },
1818
1819 #ifdef LOCK_DEBUG
1820         {
1821                 {"trace_lock_oidmin", PGC_SUSET, DEVELOPER_OPTIONS,
1822                         gettext_noop("No description available."),
1823                         NULL,
1824                         GUC_NOT_IN_SAMPLE
1825                 },
1826                 &Trace_lock_oidmin,
1827                 FirstNormalObjectId, 0, INT_MAX,
1828                 NULL, NULL, NULL
1829         },
1830         {
1831                 {"trace_lock_table", PGC_SUSET, DEVELOPER_OPTIONS,
1832                         gettext_noop("No description available."),
1833                         NULL,
1834                         GUC_NOT_IN_SAMPLE
1835                 },
1836                 &Trace_lock_table,
1837                 0, 0, INT_MAX,
1838                 NULL, NULL, NULL
1839         },
1840 #endif
1841
1842         {
1843                 {"statement_timeout", PGC_USERSET, CLIENT_CONN_STATEMENT,
1844                         gettext_noop("Sets the maximum allowed duration of any statement."),
1845                         gettext_noop("A value of 0 turns off the timeout."),
1846                         GUC_UNIT_MS
1847                 },
1848                 &StatementTimeout,
1849                 0, 0, INT_MAX,
1850                 NULL, NULL, NULL
1851         },
1852
1853         {
1854                 {"vacuum_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
1855                         gettext_noop("Minimum age at which VACUUM should freeze a table row."),
1856                         NULL
1857                 },
1858                 &vacuum_freeze_min_age,
1859                 50000000, 0, 1000000000,
1860                 NULL, NULL, NULL
1861         },
1862
1863         {
1864                 {"vacuum_freeze_table_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
1865                         gettext_noop("Age at which VACUUM should scan whole table to freeze tuples."),
1866                         NULL
1867                 },
1868                 &vacuum_freeze_table_age,
1869                 150000000, 0, 2000000000,
1870                 NULL, NULL, NULL
1871         },
1872
1873         {
1874                 {"vacuum_defer_cleanup_age", PGC_SIGHUP, REPLICATION_MASTER,
1875                         gettext_noop("Number of transactions by which VACUUM and HOT cleanup should be deferred, if any."),
1876                         NULL
1877                 },
1878                 &vacuum_defer_cleanup_age,
1879                 0, 0, 1000000,
1880                 NULL, NULL, NULL
1881         },
1882
1883         /*
1884          * See also CheckRequiredParameterValues() if this parameter changes
1885          */
1886         {
1887                 {"max_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT,
1888                         gettext_noop("Sets the maximum number of locks per transaction."),
1889                         gettext_noop("The shared lock table is sized on the assumption that "
1890                           "at most max_locks_per_transaction * max_connections distinct "
1891                                                  "objects will need to be locked at any one time.")
1892                 },
1893                 &max_locks_per_xact,
1894                 64, 10, INT_MAX,
1895                 NULL, NULL, NULL
1896         },
1897
1898         {
1899                 {"max_pred_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT,
1900                         gettext_noop("Sets the maximum number of predicate locks per transaction."),
1901                         gettext_noop("The shared predicate lock table is sized on the assumption that "
1902                                                  "at most max_pred_locks_per_transaction * max_connections distinct "
1903                                                  "objects will need to be locked at any one time.")
1904                 },
1905                 &max_predicate_locks_per_xact,
1906                 64, 10, INT_MAX,
1907                 NULL, NULL, NULL
1908         },
1909
1910         {
1911                 {"authentication_timeout", PGC_SIGHUP, CONN_AUTH_SECURITY,
1912                         gettext_noop("Sets the maximum allowed time to complete client authentication."),
1913                         NULL,
1914                         GUC_UNIT_S
1915                 },
1916                 &AuthenticationTimeout,
1917                 60, 1, 600,
1918                 NULL, NULL, NULL
1919         },
1920
1921         {
1922                 /* Not for general use */
1923                 {"pre_auth_delay", PGC_SIGHUP, DEVELOPER_OPTIONS,
1924                         gettext_noop("Waits N seconds on connection startup before authentication."),
1925                         gettext_noop("This allows attaching a debugger to the process."),
1926                         GUC_NOT_IN_SAMPLE | GUC_UNIT_S
1927                 },
1928                 &PreAuthDelay,
1929                 0, 0, 60,
1930                 NULL, NULL, NULL
1931         },
1932
1933         {
1934                 {"wal_keep_segments", PGC_SIGHUP, REPLICATION_SENDING,
1935                         gettext_noop("Sets the number of WAL files held for standby servers."),
1936                         NULL
1937                 },
1938                 &wal_keep_segments,
1939                 0, 0, INT_MAX,
1940                 NULL, NULL, NULL
1941         },
1942
1943         {
1944                 {"checkpoint_segments", PGC_SIGHUP, WAL_CHECKPOINTS,
1945                         gettext_noop("Sets the maximum distance in log segments between automatic WAL checkpoints."),
1946                         NULL
1947                 },
1948                 &CheckPointSegments,
1949                 3, 1, INT_MAX,
1950                 NULL, NULL, NULL
1951         },
1952
1953         {
1954                 {"checkpoint_timeout", PGC_SIGHUP, WAL_CHECKPOINTS,
1955                         gettext_noop("Sets the maximum time between automatic WAL checkpoints."),
1956                         NULL,
1957                         GUC_UNIT_S
1958                 },
1959                 &CheckPointTimeout,
1960                 300, 30, 3600,
1961                 NULL, NULL, NULL
1962         },
1963
1964         {
1965                 {"checkpoint_warning", PGC_SIGHUP, WAL_CHECKPOINTS,
1966                         gettext_noop("Enables warnings if checkpoint segments are filled more "
1967                                                  "frequently than this."),
1968                         gettext_noop("Write a message to the server log if checkpoints "
1969                         "caused by the filling of checkpoint segment files happens more "
1970                                                  "frequently than this number of seconds. Zero turns off the warning."),
1971                         GUC_UNIT_S
1972                 },
1973                 &CheckPointWarning,
1974                 30, 0, INT_MAX,
1975                 NULL, NULL, NULL
1976         },
1977
1978         {
1979                 {"wal_buffers", PGC_POSTMASTER, WAL_SETTINGS,
1980                         gettext_noop("Sets the number of disk-page buffers in shared memory for WAL."),
1981                         NULL,
1982                         GUC_UNIT_XBLOCKS
1983                 },
1984                 &XLOGbuffers,
1985                 -1, -1, INT_MAX,
1986                 check_wal_buffers, NULL, NULL
1987         },
1988
1989         {
1990                 {"wal_writer_delay", PGC_SIGHUP, WAL_SETTINGS,
1991                         gettext_noop("WAL writer sleep time between WAL flushes."),
1992                         NULL,
1993                         GUC_UNIT_MS
1994                 },
1995                 &WalWriterDelay,
1996                 200, 1, 10000,
1997                 NULL, NULL, NULL
1998         },
1999
2000         {
2001                 /* see max_connections */
2002                 {"max_wal_senders", PGC_POSTMASTER, REPLICATION_SENDING,
2003                         gettext_noop("Sets the maximum number of simultaneously running WAL sender processes."),
2004                         NULL
2005                 },
2006                 &max_wal_senders,
2007                 0, 0, MAX_BACKENDS,
2008                 NULL, NULL, NULL
2009         },
2010
2011         {
2012                 {"replication_timeout", PGC_SIGHUP, REPLICATION_SENDING,
2013                         gettext_noop("Sets the maximum time to wait for WAL replication."),
2014                         NULL,
2015                         GUC_UNIT_MS
2016                 },
2017                 &replication_timeout,
2018                 60 * 1000, 0, INT_MAX,
2019                 NULL, NULL, NULL
2020         },
2021
2022         {
2023                 {"commit_delay", PGC_USERSET, WAL_SETTINGS,
2024                         gettext_noop("Sets the delay in microseconds between transaction commit and "
2025                                                  "flushing WAL to disk."),
2026                         NULL
2027                 },
2028                 &CommitDelay,
2029                 0, 0, 100000,
2030                 NULL, NULL, NULL
2031         },
2032
2033         {
2034                 {"commit_siblings", PGC_USERSET, WAL_SETTINGS,
2035                         gettext_noop("Sets the minimum concurrent open transactions before performing "
2036                                                  "commit_delay."),
2037                         NULL
2038                 },
2039                 &CommitSiblings,
2040                 5, 0, 1000,
2041                 NULL, NULL, NULL
2042         },
2043
2044         {
2045                 {"extra_float_digits", PGC_USERSET, CLIENT_CONN_LOCALE,
2046                         gettext_noop("Sets the number of digits displayed for floating-point values."),
2047                         gettext_noop("This affects real, double precision, and geometric data types. "
2048                          "The parameter value is added to the standard number of digits "
2049                                                  "(FLT_DIG or DBL_DIG as appropriate).")
2050                 },
2051                 &extra_float_digits,
2052                 0, -15, 3,
2053                 NULL, NULL, NULL
2054         },
2055
2056         {
2057                 {"log_min_duration_statement", PGC_SUSET, LOGGING_WHEN,
2058                         gettext_noop("Sets the minimum execution time above which "
2059                                                  "statements will be logged."),
2060                         gettext_noop("Zero prints all queries. -1 turns this feature off."),
2061                         GUC_UNIT_MS
2062                 },
2063                 &log_min_duration_statement,
2064                 -1, -1, INT_MAX,
2065                 NULL, NULL, NULL
2066         },
2067
2068         {
2069                 {"log_autovacuum_min_duration", PGC_SIGHUP, LOGGING_WHAT,
2070                         gettext_noop("Sets the minimum execution time above which "
2071                                                  "autovacuum actions will be logged."),
2072                         gettext_noop("Zero prints all actions. -1 turns autovacuum logging off."),
2073                         GUC_UNIT_MS
2074                 },
2075                 &Log_autovacuum_min_duration,
2076                 -1, -1, INT_MAX,
2077                 NULL, NULL, NULL
2078         },
2079
2080         {
2081                 {"bgwriter_delay", PGC_SIGHUP, RESOURCES_BGWRITER,
2082                         gettext_noop("Background writer sleep time between rounds."),
2083                         NULL,
2084                         GUC_UNIT_MS
2085                 },
2086                 &BgWriterDelay,
2087                 200, 10, 10000,
2088                 NULL, NULL, NULL
2089         },
2090
2091         {
2092                 {"bgwriter_lru_maxpages", PGC_SIGHUP, RESOURCES_BGWRITER,
2093                         gettext_noop("Background writer maximum number of LRU pages to flush per round."),
2094                         NULL
2095                 },
2096                 &bgwriter_lru_maxpages,
2097                 100, 0, 1000,
2098                 NULL, NULL, NULL
2099         },
2100
2101         {
2102                 {"effective_io_concurrency",
2103 #ifdef USE_PREFETCH
2104                         PGC_USERSET,
2105 #else
2106                         PGC_INTERNAL,
2107 #endif
2108                         RESOURCES_ASYNCHRONOUS,
2109                         gettext_noop("Number of simultaneous requests that can be handled efficiently by the disk subsystem."),
2110                         gettext_noop("For RAID arrays, this should be approximately the number of drive spindles in the array.")
2111                 },
2112                 &effective_io_concurrency,
2113 #ifdef USE_PREFETCH
2114                 1, 0, 1000,
2115 #else
2116                 0, 0, 0,
2117 #endif
2118                 check_effective_io_concurrency, assign_effective_io_concurrency, NULL
2119         },
2120
2121         {
2122                 {"log_rotation_age", PGC_SIGHUP, LOGGING_WHERE,
2123                         gettext_noop("Automatic log file rotation will occur after N minutes."),
2124                         NULL,
2125                         GUC_UNIT_MIN
2126                 },
2127                 &Log_RotationAge,
2128                 HOURS_PER_DAY * MINS_PER_HOUR, 0, INT_MAX / MINS_PER_HOUR,
2129                 NULL, NULL, NULL
2130         },
2131
2132         {
2133                 {"log_rotation_size", PGC_SIGHUP, LOGGING_WHERE,
2134                         gettext_noop("Automatic log file rotation will occur after N kilobytes."),
2135                         NULL,
2136                         GUC_UNIT_KB
2137                 },
2138                 &Log_RotationSize,
2139                 10 * 1024, 0, INT_MAX / 1024,
2140                 NULL, NULL, NULL
2141         },
2142
2143         {
2144                 {"max_function_args", PGC_INTERNAL, PRESET_OPTIONS,
2145                         gettext_noop("Shows the maximum number of function arguments."),
2146                         NULL,
2147                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2148                 },
2149                 &max_function_args,
2150                 FUNC_MAX_ARGS, FUNC_MAX_ARGS, FUNC_MAX_ARGS,
2151                 NULL, NULL, NULL
2152         },
2153
2154         {
2155                 {"max_index_keys", PGC_INTERNAL, PRESET_OPTIONS,
2156                         gettext_noop("Shows the maximum number of index keys."),
2157                         NULL,
2158                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2159                 },
2160                 &max_index_keys,
2161                 INDEX_MAX_KEYS, INDEX_MAX_KEYS, INDEX_MAX_KEYS,
2162                 NULL, NULL, NULL
2163         },
2164
2165         {
2166                 {"max_identifier_length", PGC_INTERNAL, PRESET_OPTIONS,
2167                         gettext_noop("Shows the maximum identifier length."),
2168                         NULL,
2169                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2170                 },
2171                 &max_identifier_length,
2172                 NAMEDATALEN - 1, NAMEDATALEN - 1, NAMEDATALEN - 1,
2173                 NULL, NULL, NULL
2174         },
2175
2176         {
2177                 {"block_size", PGC_INTERNAL, PRESET_OPTIONS,
2178                         gettext_noop("Shows the size of a disk block."),
2179                         NULL,
2180                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2181                 },
2182                 &block_size,
2183                 BLCKSZ, BLCKSZ, BLCKSZ,
2184                 NULL, NULL, NULL
2185         },
2186
2187         {
2188                 {"segment_size", PGC_INTERNAL, PRESET_OPTIONS,
2189                         gettext_noop("Shows the number of pages per disk file."),
2190                         NULL,
2191                         GUC_UNIT_BLOCKS | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2192                 },
2193                 &segment_size,
2194                 RELSEG_SIZE, RELSEG_SIZE, RELSEG_SIZE,
2195                 NULL, NULL, NULL
2196         },
2197
2198         {
2199                 {"wal_block_size", PGC_INTERNAL, PRESET_OPTIONS,
2200                         gettext_noop("Shows the block size in the write ahead log."),
2201                         NULL,
2202                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2203                 },
2204                 &wal_block_size,
2205                 XLOG_BLCKSZ, XLOG_BLCKSZ, XLOG_BLCKSZ,
2206                 NULL, NULL, NULL
2207         },
2208
2209         {
2210                 {"wal_segment_size", PGC_INTERNAL, PRESET_OPTIONS,
2211                         gettext_noop("Shows the number of pages per write ahead log segment."),
2212                         NULL,
2213                         GUC_UNIT_XBLOCKS | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2214                 },
2215                 &wal_segment_size,
2216                 (XLOG_SEG_SIZE / XLOG_BLCKSZ),
2217                 (XLOG_SEG_SIZE / XLOG_BLCKSZ),
2218                 (XLOG_SEG_SIZE / XLOG_BLCKSZ),
2219                 NULL, NULL, NULL
2220         },
2221
2222         {
2223                 {"autovacuum_naptime", PGC_SIGHUP, AUTOVACUUM,
2224                         gettext_noop("Time to sleep between autovacuum runs."),
2225                         NULL,
2226                         GUC_UNIT_S
2227                 },
2228                 &autovacuum_naptime,
2229                 60, 1, INT_MAX / 1000,
2230                 NULL, NULL, NULL
2231         },
2232         {
2233                 {"autovacuum_vacuum_threshold", PGC_SIGHUP, AUTOVACUUM,
2234                         gettext_noop("Minimum number of tuple updates or deletes prior to vacuum."),
2235                         NULL
2236                 },
2237                 &autovacuum_vac_thresh,
2238                 50, 0, INT_MAX,
2239                 NULL, NULL, NULL
2240         },
2241         {
2242                 {"autovacuum_analyze_threshold", PGC_SIGHUP, AUTOVACUUM,
2243                         gettext_noop("Minimum number of tuple inserts, updates or deletes prior to analyze."),
2244                         NULL
2245                 },
2246                 &autovacuum_anl_thresh,
2247                 50, 0, INT_MAX,
2248                 NULL, NULL, NULL
2249         },
2250         {
2251                 /* see varsup.c for why this is PGC_POSTMASTER not PGC_SIGHUP */
2252                 {"autovacuum_freeze_max_age", PGC_POSTMASTER, AUTOVACUUM,
2253                         gettext_noop("Age at which to autovacuum a table to prevent transaction ID wraparound."),
2254                         NULL
2255                 },
2256                 &autovacuum_freeze_max_age,
2257                 /* see pg_resetxlog if you change the upper-limit value */
2258                 200000000, 100000000, 2000000000,
2259                 NULL, NULL, NULL
2260         },
2261         {
2262                 /* see max_connections */
2263                 {"autovacuum_max_workers", PGC_POSTMASTER, AUTOVACUUM,
2264                         gettext_noop("Sets the maximum number of simultaneously running autovacuum worker processes."),
2265                         NULL
2266                 },
2267                 &autovacuum_max_workers,
2268                 3, 1, MAX_BACKENDS,
2269                 check_autovacuum_max_workers, assign_autovacuum_max_workers, NULL
2270         },
2271
2272         {
2273                 {"tcp_keepalives_idle", PGC_USERSET, CLIENT_CONN_OTHER,
2274                         gettext_noop("Time between issuing TCP keepalives."),
2275                         gettext_noop("A value of 0 uses the system default."),
2276                         GUC_UNIT_S
2277                 },
2278                 &tcp_keepalives_idle,
2279                 0, 0, INT_MAX,
2280                 NULL, assign_tcp_keepalives_idle, show_tcp_keepalives_idle
2281         },
2282
2283         {
2284                 {"tcp_keepalives_interval", PGC_USERSET, CLIENT_CONN_OTHER,
2285                         gettext_noop("Time between TCP keepalive retransmits."),
2286                         gettext_noop("A value of 0 uses the system default."),
2287                         GUC_UNIT_S
2288                 },
2289                 &tcp_keepalives_interval,
2290                 0, 0, INT_MAX,
2291                 NULL, assign_tcp_keepalives_interval, show_tcp_keepalives_interval
2292         },
2293
2294         {
2295                 {"ssl_renegotiation_limit", PGC_USERSET, CONN_AUTH_SECURITY,
2296                         gettext_noop("Set the amount of traffic to send and receive before renegotiating the encryption keys."),
2297                         NULL,
2298                         GUC_UNIT_KB,
2299                 },
2300                 &ssl_renegotiation_limit,
2301                 512 * 1024, 0, MAX_KILOBYTES,
2302                 NULL, NULL, NULL
2303         },
2304
2305         {
2306                 {"tcp_keepalives_count", PGC_USERSET, CLIENT_CONN_OTHER,
2307                         gettext_noop("Maximum number of TCP keepalive retransmits."),
2308                         gettext_noop("This controls the number of consecutive keepalive retransmits that can be "
2309                                                  "lost before a connection is considered dead. A value of 0 uses the "
2310                                                  "system default."),
2311                 },
2312                 &tcp_keepalives_count,
2313                 0, 0, INT_MAX,
2314                 NULL, assign_tcp_keepalives_count, show_tcp_keepalives_count
2315         },
2316
2317         {
2318                 {"gin_fuzzy_search_limit", PGC_USERSET, CLIENT_CONN_OTHER,
2319                         gettext_noop("Sets the maximum allowed result for exact search by GIN."),
2320                         NULL,
2321                         0
2322                 },
2323                 &GinFuzzySearchLimit,
2324                 0, 0, INT_MAX,
2325                 NULL, NULL, NULL
2326         },
2327
2328         {
2329                 {"effective_cache_size", PGC_USERSET, QUERY_TUNING_COST,
2330                         gettext_noop("Sets the planner's assumption about the size of the disk cache."),
2331                         gettext_noop("That is, the portion of the kernel's disk cache that "
2332                                                  "will be used for PostgreSQL data files. This is measured in disk "
2333                                                  "pages, which are normally 8 kB each."),
2334                         GUC_UNIT_BLOCKS,
2335                 },
2336                 &effective_cache_size,
2337                 DEFAULT_EFFECTIVE_CACHE_SIZE, 1, INT_MAX,
2338                 NULL, NULL, NULL
2339         },
2340
2341         {
2342                 /* Can't be set in postgresql.conf */
2343                 {"server_version_num", PGC_INTERNAL, PRESET_OPTIONS,
2344                         gettext_noop("Shows the server version as an integer."),
2345                         NULL,
2346                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2347                 },
2348                 &server_version_num,
2349                 PG_VERSION_NUM, PG_VERSION_NUM, PG_VERSION_NUM,
2350                 NULL, NULL, NULL
2351         },
2352
2353         {
2354                 {"log_temp_files", PGC_SUSET, LOGGING_WHAT,
2355                         gettext_noop("Log the use of temporary files larger than this number of kilobytes."),
2356                         gettext_noop("Zero logs all files. The default is -1 (turning this feature off)."),
2357                         GUC_UNIT_KB
2358                 },
2359                 &log_temp_files,
2360                 -1, -1, INT_MAX,
2361                 NULL, NULL, NULL
2362         },
2363
2364         {
2365                 {"track_activity_query_size", PGC_POSTMASTER, RESOURCES_MEM,
2366                         gettext_noop("Sets the size reserved for pg_stat_activity.query, in bytes."),
2367                         NULL,
2368                 },
2369                 &pgstat_track_activity_query_size,
2370                 1024, 100, 102400,
2371                 NULL, NULL, NULL
2372         },
2373
2374         /* End-of-list marker */
2375         {
2376                 {NULL, 0, 0, NULL, NULL}, NULL, 0, 0, 0, NULL, NULL, NULL
2377         }
2378 };
2379
2380
2381 static struct config_real ConfigureNamesReal[] =
2382 {
2383         {
2384                 {"seq_page_cost", PGC_USERSET, QUERY_TUNING_COST,
2385                         gettext_noop("Sets the planner's estimate of the cost of a "
2386                                                  "sequentially fetched disk page."),
2387                         NULL
2388                 },
2389                 &seq_page_cost,
2390                 DEFAULT_SEQ_PAGE_COST, 0, DBL_MAX,
2391                 NULL, NULL, NULL
2392         },
2393         {
2394                 {"random_page_cost", PGC_USERSET, QUERY_TUNING_COST,
2395                         gettext_noop("Sets the planner's estimate of the cost of a "
2396                                                  "nonsequentially fetched disk page."),
2397                         NULL
2398                 },
2399                 &random_page_cost,
2400                 DEFAULT_RANDOM_PAGE_COST, 0, DBL_MAX,
2401                 NULL, NULL, NULL
2402         },
2403         {
2404                 {"cpu_tuple_cost", PGC_USERSET, QUERY_TUNING_COST,
2405                         gettext_noop("Sets the planner's estimate of the cost of "
2406                                                  "processing each tuple (row)."),
2407                         NULL
2408                 },
2409                 &cpu_tuple_cost,
2410                 DEFAULT_CPU_TUPLE_COST, 0, DBL_MAX,
2411                 NULL, NULL, NULL
2412         },
2413         {
2414                 {"cpu_index_tuple_cost", PGC_USERSET, QUERY_TUNING_COST,
2415                         gettext_noop("Sets the planner's estimate of the cost of "
2416                                                  "processing each index entry during an index scan."),
2417                         NULL
2418                 },
2419                 &cpu_index_tuple_cost,
2420                 DEFAULT_CPU_INDEX_TUPLE_COST, 0, DBL_MAX,
2421                 NULL, NULL, NULL
2422         },
2423         {
2424                 {"cpu_operator_cost", PGC_USERSET, QUERY_TUNING_COST,
2425                         gettext_noop("Sets the planner's estimate of the cost of "
2426                                                  "processing each operator or function call."),
2427                         NULL
2428                 },
2429                 &cpu_operator_cost,
2430                 DEFAULT_CPU_OPERATOR_COST, 0, DBL_MAX,
2431                 NULL, NULL, NULL
2432         },
2433
2434         {
2435                 {"cursor_tuple_fraction", PGC_USERSET, QUERY_TUNING_OTHER,
2436                         gettext_noop("Sets the planner's estimate of the fraction of "
2437                                                  "a cursor's rows that will be retrieved."),
2438                         NULL
2439                 },
2440                 &cursor_tuple_fraction,
2441                 DEFAULT_CURSOR_TUPLE_FRACTION, 0.0, 1.0,
2442                 NULL, NULL, NULL
2443         },
2444
2445         {
2446                 {"geqo_selection_bias", PGC_USERSET, QUERY_TUNING_GEQO,
2447                         gettext_noop("GEQO: selective pressure within the population."),
2448                         NULL
2449                 },
2450                 &Geqo_selection_bias,
2451                 DEFAULT_GEQO_SELECTION_BIAS,
2452                 MIN_GEQO_SELECTION_BIAS, MAX_GEQO_SELECTION_BIAS,
2453                 NULL, NULL, NULL
2454         },
2455         {
2456                 {"geqo_seed", PGC_USERSET, QUERY_TUNING_GEQO,
2457                         gettext_noop("GEQO: seed for random path selection."),
2458                         NULL
2459                 },
2460                 &Geqo_seed,
2461                 0.0, 0.0, 1.0,
2462                 NULL, NULL, NULL
2463         },
2464
2465         {
2466                 {"bgwriter_lru_multiplier", PGC_SIGHUP, RESOURCES_BGWRITER,
2467                         gettext_noop("Multiple of the average buffer usage to free per round."),
2468                         NULL
2469                 },
2470                 &bgwriter_lru_multiplier,
2471                 2.0, 0.0, 10.0,
2472                 NULL, NULL, NULL
2473         },
2474
2475         {
2476                 {"seed", PGC_USERSET, UNGROUPED,
2477                         gettext_noop("Sets the seed for random-number generation."),
2478                         NULL,
2479                         GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2480                 },
2481                 &phony_random_seed,
2482                 0.0, -1.0, 1.0,
2483                 check_random_seed, assign_random_seed, show_random_seed
2484         },
2485
2486         {
2487                 {"autovacuum_vacuum_scale_factor", PGC_SIGHUP, AUTOVACUUM,
2488                         gettext_noop("Number of tuple updates or deletes prior to vacuum as a fraction of reltuples."),
2489                         NULL
2490                 },
2491                 &autovacuum_vac_scale,
2492                 0.2, 0.0, 100.0,
2493                 NULL, NULL, NULL
2494         },
2495         {
2496                 {"autovacuum_analyze_scale_factor", PGC_SIGHUP, AUTOVACUUM,
2497                         gettext_noop("Number of tuple inserts, updates or deletes prior to analyze as a fraction of reltuples."),
2498                         NULL
2499                 },
2500                 &autovacuum_anl_scale,
2501                 0.1, 0.0, 100.0,
2502                 NULL, NULL, NULL
2503         },
2504
2505         {
2506                 {"checkpoint_completion_target", PGC_SIGHUP, WAL_CHECKPOINTS,
2507                         gettext_noop("Time spent flushing dirty buffers during checkpoint, as fraction of checkpoint interval."),
2508                         NULL
2509                 },
2510                 &CheckPointCompletionTarget,
2511                 0.5, 0.0, 1.0,
2512                 NULL, NULL, NULL
2513         },
2514
2515         /* End-of-list marker */
2516         {
2517                 {NULL, 0, 0, NULL, NULL}, NULL, 0.0, 0.0, 0.0, NULL, NULL, NULL
2518         }
2519 };
2520
2521
2522 static struct config_string ConfigureNamesString[] =
2523 {
2524         {
2525                 {"archive_command", PGC_SIGHUP, WAL_ARCHIVING,
2526                         gettext_noop("Sets the shell command that will be called to archive a WAL file."),
2527                         NULL
2528                 },
2529                 &XLogArchiveCommand,
2530                 "",
2531                 NULL, NULL, show_archive_command
2532         },
2533
2534         {
2535                 {"client_encoding", PGC_USERSET, CLIENT_CONN_LOCALE,
2536                         gettext_noop("Sets the client's character set encoding."),
2537                         NULL,
2538                         GUC_IS_NAME | GUC_REPORT
2539                 },
2540                 &client_encoding_string,
2541                 "SQL_ASCII",
2542                 check_client_encoding, assign_client_encoding, NULL
2543         },
2544
2545         {
2546                 {"log_line_prefix", PGC_SIGHUP, LOGGING_WHAT,
2547                         gettext_noop("Controls information prefixed to each log line."),
2548                         gettext_noop("If blank, no prefix is used.")
2549                 },
2550                 &Log_line_prefix,
2551                 "",
2552                 NULL, NULL, NULL
2553         },
2554
2555         {
2556                 {"log_timezone", PGC_SIGHUP, LOGGING_WHAT,
2557                         gettext_noop("Sets the time zone to use in log messages."),
2558                         NULL
2559                 },
2560                 &log_timezone_string,
2561                 "GMT",
2562                 check_log_timezone, assign_log_timezone, show_log_timezone
2563         },
2564
2565         {
2566                 {"DateStyle", PGC_USERSET, CLIENT_CONN_LOCALE,
2567                         gettext_noop("Sets the display format for date and time values."),
2568                         gettext_noop("Also controls interpretation of ambiguous "
2569                                                  "date inputs."),
2570                         GUC_LIST_INPUT | GUC_REPORT
2571                 },
2572                 &datestyle_string,
2573                 "ISO, MDY",
2574                 check_datestyle, assign_datestyle, NULL
2575         },
2576
2577         {
2578                 {"default_tablespace", PGC_USERSET, CLIENT_CONN_STATEMENT,
2579                         gettext_noop("Sets the default tablespace to create tables and indexes in."),
2580                         gettext_noop("An empty string selects the database's default tablespace."),
2581                         GUC_IS_NAME
2582                 },
2583                 &default_tablespace,
2584                 "",
2585                 check_default_tablespace, NULL, NULL
2586         },
2587
2588         {
2589                 {"temp_tablespaces", PGC_USERSET, CLIENT_CONN_STATEMENT,
2590                         gettext_noop("Sets the tablespace(s) to use for temporary tables and sort files."),
2591                         NULL,
2592                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2593                 },
2594                 &temp_tablespaces,
2595                 "",
2596                 check_temp_tablespaces, assign_temp_tablespaces, NULL
2597         },
2598
2599         {
2600                 {"dynamic_library_path", PGC_SUSET, CLIENT_CONN_OTHER,
2601                         gettext_noop("Sets the path for dynamically loadable modules."),
2602                         gettext_noop("If a dynamically loadable module needs to be opened and "
2603                                                  "the specified name does not have a directory component (i.e., the "
2604                                                  "name does not contain a slash), the system will search this path for "
2605                                                  "the specified file."),
2606                         GUC_SUPERUSER_ONLY
2607                 },
2608                 &Dynamic_library_path,
2609                 "$libdir",
2610                 NULL, NULL, NULL
2611         },
2612
2613         {
2614                 {"krb_server_keyfile", PGC_SIGHUP, CONN_AUTH_SECURITY,
2615                         gettext_noop("Sets the location of the Kerberos server key file."),
2616                         NULL,
2617                         GUC_SUPERUSER_ONLY
2618                 },
2619                 &pg_krb_server_keyfile,
2620                 PG_KRB_SRVTAB,
2621                 NULL, NULL, NULL
2622         },
2623
2624         {
2625                 {"krb_srvname", PGC_SIGHUP, CONN_AUTH_SECURITY,
2626                         gettext_noop("Sets the name of the Kerberos service."),
2627                         NULL
2628                 },
2629                 &pg_krb_srvnam,
2630                 PG_KRB_SRVNAM,
2631                 NULL, NULL, NULL
2632         },
2633
2634         {
2635                 {"bonjour_name", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2636                         gettext_noop("Sets the Bonjour service name."),
2637                         NULL
2638                 },
2639                 &bonjour_name,
2640                 "",
2641                 NULL, NULL, NULL
2642         },
2643
2644         /* See main.c about why defaults for LC_foo are not all alike */
2645
2646         {
2647                 {"lc_collate", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2648                         gettext_noop("Shows the collation order locale."),
2649                         NULL,
2650                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2651                 },
2652                 &locale_collate,
2653                 "C",
2654                 NULL, NULL, NULL
2655         },
2656
2657         {
2658                 {"lc_ctype", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2659                         gettext_noop("Shows the character classification and case conversion locale."),
2660                         NULL,
2661                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2662                 },
2663                 &locale_ctype,
2664                 "C",
2665                 NULL, NULL, NULL
2666         },
2667
2668         {
2669                 {"lc_messages", PGC_SUSET, CLIENT_CONN_LOCALE,
2670                         gettext_noop("Sets the language in which messages are displayed."),
2671                         NULL
2672                 },
2673                 &locale_messages,
2674                 "",
2675                 check_locale_messages, assign_locale_messages, NULL
2676         },
2677
2678         {
2679                 {"lc_monetary", PGC_USERSET, CLIENT_CONN_LOCALE,
2680                         gettext_noop("Sets the locale for formatting monetary amounts."),
2681                         NULL
2682                 },
2683                 &locale_monetary,
2684                 "C",
2685                 check_locale_monetary, assign_locale_monetary, NULL
2686         },
2687
2688         {
2689                 {"lc_numeric", PGC_USERSET, CLIENT_CONN_LOCALE,
2690                         gettext_noop("Sets the locale for formatting numbers."),
2691                         NULL
2692                 },
2693                 &locale_numeric,
2694                 "C",
2695                 check_locale_numeric, assign_locale_numeric, NULL
2696         },
2697
2698         {
2699                 {"lc_time", PGC_USERSET, CLIENT_CONN_LOCALE,
2700                         gettext_noop("Sets the locale for formatting date and time values."),
2701                         NULL
2702                 },
2703                 &locale_time,
2704                 "C",
2705                 check_locale_time, assign_locale_time, NULL
2706         },
2707
2708         {
2709                 {"shared_preload_libraries", PGC_POSTMASTER, RESOURCES_KERNEL,
2710                         gettext_noop("Lists shared libraries to preload into server."),
2711                         NULL,
2712                         GUC_LIST_INPUT | GUC_LIST_QUOTE | GUC_SUPERUSER_ONLY
2713                 },
2714                 &shared_preload_libraries_string,
2715                 "",
2716                 NULL, NULL, NULL
2717         },
2718
2719         {
2720                 {"local_preload_libraries", PGC_BACKEND, CLIENT_CONN_OTHER,
2721                         gettext_noop("Lists shared libraries to preload into each backend."),
2722                         NULL,
2723                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2724                 },
2725                 &local_preload_libraries_string,
2726                 "",
2727                 NULL, NULL, NULL
2728         },
2729
2730         {
2731                 {"search_path", PGC_USERSET, CLIENT_CONN_STATEMENT,
2732                         gettext_noop("Sets the schema search order for names that are not schema-qualified."),
2733                         NULL,
2734                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2735                 },
2736                 &namespace_search_path,
2737                 "\"$user\",public",
2738                 check_search_path, assign_search_path, NULL
2739         },
2740
2741         {
2742                 /* Can't be set in postgresql.conf */
2743                 {"server_encoding", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2744                         gettext_noop("Sets the server (database) character set encoding."),
2745                         NULL,
2746                         GUC_IS_NAME | GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2747                 },
2748                 &server_encoding_string,
2749                 "SQL_ASCII",
2750                 NULL, NULL, NULL
2751         },
2752
2753         {
2754                 /* Can't be set in postgresql.conf */
2755                 {"server_version", PGC_INTERNAL, PRESET_OPTIONS,
2756                         gettext_noop("Shows the server version."),
2757                         NULL,
2758                         GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2759                 },
2760                 &server_version_string,
2761                 PG_VERSION,
2762                 NULL, NULL, NULL
2763         },
2764
2765         {
2766                 /* Not for general use --- used by SET ROLE */
2767                 {"role", PGC_USERSET, UNGROUPED,
2768                         gettext_noop("Sets the current role."),
2769                         NULL,
2770                         GUC_IS_NAME | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE | GUC_NOT_WHILE_SEC_REST
2771                 },
2772                 &role_string,
2773                 "none",
2774                 check_role, assign_role, show_role
2775         },
2776
2777         {
2778                 /* Not for general use --- used by SET SESSION AUTHORIZATION */
2779                 {"session_authorization", PGC_USERSET, UNGROUPED,
2780                         gettext_noop("Sets the session user name."),
2781                         NULL,
2782                         GUC_IS_NAME | GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE | GUC_NOT_WHILE_SEC_REST
2783                 },
2784                 &session_authorization_string,
2785                 NULL,
2786                 check_session_authorization, assign_session_authorization, NULL
2787         },
2788
2789         {
2790                 {"log_destination", PGC_SIGHUP, LOGGING_WHERE,
2791                         gettext_noop("Sets the destination for server log output."),
2792                         gettext_noop("Valid values are combinations of \"stderr\", "
2793                                                  "\"syslog\", \"csvlog\", and \"eventlog\", "
2794                                                  "depending on the platform."),
2795                         GUC_LIST_INPUT
2796                 },
2797                 &log_destination_string,
2798                 "stderr",
2799                 check_log_destination, assign_log_destination, NULL
2800         },
2801         {
2802                 {"log_directory", PGC_SIGHUP, LOGGING_WHERE,
2803                         gettext_noop("Sets the destination directory for log files."),
2804                         gettext_noop("Can be specified as relative to the data directory "
2805                                                  "or as absolute path."),
2806                         GUC_SUPERUSER_ONLY
2807                 },
2808                 &Log_directory,
2809                 "pg_log",
2810                 check_canonical_path, NULL, NULL
2811         },
2812         {
2813                 {"log_filename", PGC_SIGHUP, LOGGING_WHERE,
2814                         gettext_noop("Sets the file name pattern for log files."),
2815                         NULL,
2816                         GUC_SUPERUSER_ONLY
2817                 },
2818                 &Log_filename,
2819                 "postgresql-%Y-%m-%d_%H%M%S.log",
2820                 NULL, NULL, NULL
2821         },
2822
2823         {
2824                 {"syslog_ident", PGC_SIGHUP, LOGGING_WHERE,
2825                         gettext_noop("Sets the program name used to identify PostgreSQL "
2826                                                  "messages in syslog."),
2827                         NULL
2828                 },
2829                 &syslog_ident_str,
2830                 "postgres",
2831                 NULL, assign_syslog_ident, NULL
2832         },
2833
2834         {
2835                 {"event_source", PGC_POSTMASTER, LOGGING_WHERE,
2836                         gettext_noop("Sets the application name used to identify"
2837                                                  "PostgreSQL messages in the event log."),
2838                         NULL
2839                 },
2840                 &event_source,
2841                 "PostgreSQL",
2842                 NULL, NULL, NULL
2843         },
2844
2845         {
2846                 {"TimeZone", PGC_USERSET, CLIENT_CONN_LOCALE,
2847                         gettext_noop("Sets the time zone for displaying and interpreting time stamps."),
2848                         NULL,
2849                         GUC_REPORT
2850                 },
2851                 &timezone_string,
2852                 "GMT",
2853                 check_timezone, assign_timezone, show_timezone
2854         },
2855         {
2856                 {"timezone_abbreviations", PGC_USERSET, CLIENT_CONN_LOCALE,
2857                         gettext_noop("Selects a file of time zone abbreviations."),
2858                         NULL
2859                 },
2860                 &timezone_abbreviations_string,
2861                 NULL,
2862                 check_timezone_abbreviations, assign_timezone_abbreviations, NULL
2863         },
2864
2865         {
2866                 {"transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT,
2867                         gettext_noop("Sets the current transaction's isolation level."),
2868                         NULL,
2869                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2870                 },
2871                 &XactIsoLevel_string,
2872                 "default",
2873                 check_XactIsoLevel, assign_XactIsoLevel, show_XactIsoLevel
2874         },
2875
2876         {
2877                 {"unix_socket_group", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2878                         gettext_noop("Sets the owning group of the Unix-domain socket."),
2879                         gettext_noop("The owning user of the socket is always the user "
2880                                                  "that starts the server.")
2881                 },
2882                 &Unix_socket_group,
2883                 "",
2884                 NULL, NULL, NULL
2885         },
2886
2887         {
2888                 {"unix_socket_directory", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2889                         gettext_noop("Sets the directory where the Unix-domain socket will be created."),
2890                         NULL,
2891                         GUC_SUPERUSER_ONLY
2892                 },
2893                 &UnixSocketDir,
2894                 "",
2895                 check_canonical_path, NULL, NULL
2896         },
2897
2898         {
2899                 {"listen_addresses", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2900                         gettext_noop("Sets the host name or IP address(es) to listen to."),
2901                         NULL,
2902                         GUC_LIST_INPUT
2903                 },
2904                 &ListenAddresses,
2905                 "localhost",
2906                 NULL, NULL, NULL
2907         },
2908
2909         {
2910                 {"data_directory", PGC_POSTMASTER, FILE_LOCATIONS,
2911                         gettext_noop("Sets the server's data directory."),
2912                         NULL,
2913                         GUC_SUPERUSER_ONLY
2914                 },
2915                 &data_directory,
2916                 NULL,
2917                 NULL, NULL, NULL
2918         },
2919
2920         {
2921                 {"config_file", PGC_POSTMASTER, FILE_LOCATIONS,
2922                         gettext_noop("Sets the server's main configuration file."),
2923                         NULL,
2924                         GUC_DISALLOW_IN_FILE | GUC_SUPERUSER_ONLY
2925                 },
2926                 &ConfigFileName,
2927                 NULL,
2928                 NULL, NULL, NULL
2929         },
2930
2931         {
2932                 {"hba_file", PGC_POSTMASTER, FILE_LOCATIONS,
2933                         gettext_noop("Sets the server's \"hba\" configuration file."),
2934                         NULL,
2935                         GUC_SUPERUSER_ONLY
2936                 },
2937                 &HbaFileName,
2938                 NULL,
2939                 NULL, NULL, NULL
2940         },
2941
2942         {
2943                 {"ident_file", PGC_POSTMASTER, FILE_LOCATIONS,
2944                         gettext_noop("Sets the server's \"ident\" configuration file."),
2945                         NULL,
2946                         GUC_SUPERUSER_ONLY
2947                 },
2948                 &IdentFileName,
2949                 NULL,
2950                 NULL, NULL, NULL
2951         },
2952
2953         {
2954                 {"external_pid_file", PGC_POSTMASTER, FILE_LOCATIONS,
2955                         gettext_noop("Writes the postmaster PID to the specified file."),
2956                         NULL,
2957                         GUC_SUPERUSER_ONLY
2958                 },
2959                 &external_pid_file,
2960                 NULL,
2961                 check_canonical_path, NULL, NULL
2962         },
2963
2964         {
2965                 {"stats_temp_directory", PGC_SIGHUP, STATS_COLLECTOR,
2966                         gettext_noop("Writes temporary statistics files to the specified directory."),
2967                         NULL,
2968                         GUC_SUPERUSER_ONLY
2969                 },
2970                 &pgstat_temp_directory,
2971                 "pg_stat_tmp",
2972                 check_canonical_path, assign_pgstat_temp_directory, NULL
2973         },
2974
2975         {
2976                 {"synchronous_standby_names", PGC_SIGHUP, REPLICATION_MASTER,
2977                         gettext_noop("List of names of potential synchronous standbys."),
2978                         NULL,
2979                         GUC_LIST_INPUT
2980                 },
2981                 &SyncRepStandbyNames,
2982                 "",
2983                 check_synchronous_standby_names, NULL, NULL
2984         },
2985
2986         {
2987                 {"default_text_search_config", PGC_USERSET, CLIENT_CONN_LOCALE,
2988                         gettext_noop("Sets default text search configuration."),
2989                         NULL
2990                 },
2991                 &TSCurrentConfig,
2992                 "pg_catalog.simple",
2993                 check_TSCurrentConfig, assign_TSCurrentConfig, NULL
2994         },
2995
2996         {
2997                 {"ssl_ciphers", PGC_POSTMASTER, CONN_AUTH_SECURITY,
2998                         gettext_noop("Sets the list of allowed SSL ciphers."),
2999                         NULL,
3000                         GUC_SUPERUSER_ONLY
3001                 },
3002                 &SSLCipherSuites,
3003 #ifdef USE_SSL
3004                 "ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH",
3005 #else
3006                 "none",
3007 #endif
3008                 NULL, NULL, NULL
3009         },
3010
3011         {
3012                 {"application_name", PGC_USERSET, LOGGING_WHAT,
3013                         gettext_noop("Sets the application name to be reported in statistics and logs."),
3014                         NULL,
3015                         GUC_IS_NAME | GUC_REPORT | GUC_NOT_IN_SAMPLE
3016                 },
3017                 &application_name,
3018                 "",
3019                 check_application_name, assign_application_name, NULL
3020         },
3021
3022         /* End-of-list marker */
3023         {
3024                 {NULL, 0, 0, NULL, NULL}, NULL, NULL, NULL, NULL, NULL
3025         }
3026 };
3027
3028
3029 static struct config_enum ConfigureNamesEnum[] =
3030 {
3031         {
3032                 {"backslash_quote", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
3033                         gettext_noop("Sets whether \"\\'\" is allowed in string literals."),
3034                         NULL
3035                 },
3036                 &backslash_quote,
3037                 BACKSLASH_QUOTE_SAFE_ENCODING, backslash_quote_options,
3038                 NULL, NULL, NULL
3039         },
3040
3041         {
3042                 {"bytea_output", PGC_USERSET, CLIENT_CONN_STATEMENT,
3043                         gettext_noop("Sets the output format for bytea."),
3044                         NULL
3045                 },
3046                 &bytea_output,
3047                 BYTEA_OUTPUT_HEX, bytea_output_options,
3048                 NULL, NULL, NULL
3049         },
3050
3051         {
3052                 {"client_min_messages", PGC_USERSET, LOGGING_WHEN,
3053                         gettext_noop("Sets the message levels that are sent to the client."),
3054                         gettext_noop("Each level includes all the levels that follow it. The later"
3055                                                  " the level, the fewer messages are sent.")
3056                 },
3057                 &client_min_messages,
3058                 NOTICE, client_message_level_options,
3059                 NULL, NULL, NULL
3060         },
3061
3062         {
3063                 {"constraint_exclusion", PGC_USERSET, QUERY_TUNING_OTHER,
3064                         gettext_noop("Enables the planner to use constraints to optimize queries."),
3065                         gettext_noop("Table scans will be skipped if their constraints"
3066                                                  " guarantee that no rows match the query.")
3067                 },
3068                 &constraint_exclusion,
3069                 CONSTRAINT_EXCLUSION_PARTITION, constraint_exclusion_options,
3070                 NULL, NULL, NULL
3071         },
3072
3073         {
3074                 {"default_transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT,
3075                         gettext_noop("Sets the transaction isolation level of each new transaction."),
3076                         NULL
3077                 },
3078                 &DefaultXactIsoLevel,
3079                 XACT_READ_COMMITTED, isolation_level_options,
3080                 NULL, NULL, NULL
3081         },
3082
3083         {
3084                 {"IntervalStyle", PGC_USERSET, CLIENT_CONN_LOCALE,
3085                         gettext_noop("Sets the display format for interval values."),
3086                         NULL,
3087                         GUC_REPORT
3088                 },
3089                 &IntervalStyle,
3090                 INTSTYLE_POSTGRES, intervalstyle_options,
3091                 NULL, NULL, NULL
3092         },
3093
3094         {
3095                 {"log_error_verbosity", PGC_SUSET, LOGGING_WHAT,
3096                         gettext_noop("Sets the verbosity of logged messages."),
3097                         NULL
3098                 },
3099                 &Log_error_verbosity,
3100                 PGERROR_DEFAULT, log_error_verbosity_options,
3101                 NULL, NULL, NULL
3102         },
3103
3104         {
3105                 {"log_min_messages", PGC_SUSET, LOGGING_WHEN,
3106                         gettext_noop("Sets the message levels that are logged."),
3107                         gettext_noop("Each level includes all the levels that follow it. The later"
3108                                                  " the level, the fewer messages are sent.")
3109                 },
3110                 &log_min_messages,
3111                 WARNING, server_message_level_options,
3112                 NULL, NULL, NULL
3113         },
3114
3115         {
3116                 {"log_min_error_statement", PGC_SUSET, LOGGING_WHEN,
3117                         gettext_noop("Causes all statements generating error at or above this level to be logged."),
3118                         gettext_noop("Each level includes all the levels that follow it. The later"
3119                                                  " the level, the fewer messages are sent.")
3120                 },
3121                 &log_min_error_statement,
3122                 ERROR, server_message_level_options,
3123                 NULL, NULL, NULL
3124         },
3125
3126         {
3127                 {"log_statement", PGC_SUSET, LOGGING_WHAT,
3128                         gettext_noop("Sets the type of statements logged."),
3129                         NULL
3130                 },
3131                 &log_statement,
3132                 LOGSTMT_NONE, log_statement_options,
3133                 NULL, NULL, NULL
3134         },
3135
3136         {
3137                 {"syslog_facility", PGC_SIGHUP, LOGGING_WHERE,
3138                         gettext_noop("Sets the syslog \"facility\" to be used when syslog enabled."),
3139                         NULL
3140                 },
3141                 &syslog_facility,
3142 #ifdef HAVE_SYSLOG
3143                 LOG_LOCAL0,
3144 #else
3145                 0,
3146 #endif
3147                 syslog_facility_options,
3148                 NULL, assign_syslog_facility, NULL
3149         },
3150
3151         {
3152                 {"session_replication_role", PGC_SUSET, CLIENT_CONN_STATEMENT,
3153                         gettext_noop("Sets the session's behavior for triggers and rewrite rules."),
3154                         NULL
3155                 },
3156                 &SessionReplicationRole,
3157                 SESSION_REPLICATION_ROLE_ORIGIN, session_replication_role_options,
3158                 NULL, assign_session_replication_role, NULL
3159         },
3160
3161         {
3162                 {"synchronous_commit", PGC_USERSET, WAL_SETTINGS,
3163                         gettext_noop("Sets the current transaction's synchronization level."),
3164                         NULL
3165                 },
3166                 &synchronous_commit,
3167                 SYNCHRONOUS_COMMIT_ON, synchronous_commit_options,
3168                 NULL, assign_synchronous_commit, NULL
3169         },
3170
3171         {
3172                 {"trace_recovery_messages", PGC_SIGHUP, DEVELOPER_OPTIONS,
3173                         gettext_noop("Enables logging of recovery-related debugging information."),
3174                         gettext_noop("Each level includes all the levels that follow it. The later"
3175                                                  " the level, the fewer messages are sent.")
3176                 },
3177                 &trace_recovery_messages,
3178
3179                 /*
3180                  * client_message_level_options allows too many values, really, but
3181                  * it's not worth having a separate options array for this.
3182                  */
3183                 LOG, client_message_level_options,
3184                 NULL, NULL, NULL
3185         },
3186
3187         {
3188                 {"track_functions", PGC_SUSET, STATS_COLLECTOR,
3189                         gettext_noop("Collects function-level statistics on database activity."),
3190                         NULL
3191                 },
3192                 &pgstat_track_functions,
3193                 TRACK_FUNC_OFF, track_function_options,
3194                 NULL, NULL, NULL
3195         },
3196
3197         {
3198                 {"wal_level", PGC_POSTMASTER, WAL_SETTINGS,
3199                         gettext_noop("Set the level of information written to the WAL."),
3200                         NULL
3201                 },
3202                 &wal_level,
3203                 WAL_LEVEL_MINIMAL, wal_level_options,
3204                 NULL, NULL, NULL
3205         },
3206
3207         {
3208                 {"wal_sync_method", PGC_SIGHUP, WAL_SETTINGS,
3209                         gettext_noop("Selects the method used for forcing WAL updates to disk."),
3210                         NULL
3211                 },
3212                 &sync_method,
3213                 DEFAULT_SYNC_METHOD, sync_method_options,
3214                 NULL, assign_xlog_sync_method, NULL
3215         },
3216
3217         {
3218                 {"xmlbinary", PGC_USERSET, CLIENT_CONN_STATEMENT,
3219                         gettext_noop("Sets how binary values are to be encoded in XML."),
3220                         NULL
3221                 },
3222                 &xmlbinary,
3223                 XMLBINARY_BASE64, xmlbinary_options,
3224                 NULL, NULL, NULL
3225         },
3226
3227         {
3228                 {"xmloption", PGC_USERSET, CLIENT_CONN_STATEMENT,
3229                         gettext_noop("Sets whether XML data in implicit parsing and serialization "
3230                                                  "operations is to be considered as documents or content fragments."),
3231                         NULL
3232                 },
3233                 &xmloption,
3234                 XMLOPTION_CONTENT, xmloption_options,
3235                 NULL, NULL, NULL
3236         },
3237
3238
3239         /* End-of-list marker */
3240         {
3241                 {NULL, 0, 0, NULL, NULL}, NULL, 0, NULL, NULL, NULL, NULL
3242         }
3243 };
3244
3245 /******** end of options list ********/
3246
3247
3248 /*
3249  * To allow continued support of obsolete names for GUC variables, we apply
3250  * the following mappings to any unrecognized name.  Note that an old name
3251  * should be mapped to a new one only if the new variable has very similar
3252  * semantics to the old.
3253  */
3254 static const char *const map_old_guc_names[] = {
3255         "sort_mem", "work_mem",
3256         "vacuum_mem", "maintenance_work_mem",
3257         NULL
3258 };
3259
3260
3261 /*
3262  * Actual lookup of variables is done through this single, sorted array.
3263  */
3264 static struct config_generic **guc_variables;
3265
3266 /* Current number of variables contained in the vector */
3267 static int      num_guc_variables;
3268
3269 /* Vector capacity */
3270 static int      size_guc_variables;
3271
3272
3273 static bool guc_dirty;                  /* TRUE if need to do commit/abort work */
3274
3275 static bool reporting_enabled;  /* TRUE to enable GUC_REPORT */
3276
3277 static int      GUCNestLevel = 0;       /* 1 when in main transaction */
3278
3279
3280 static int      guc_var_compare(const void *a, const void *b);
3281 static int      guc_name_compare(const char *namea, const char *nameb);
3282 static void InitializeGUCOptionsFromEnvironment(void);
3283 static void InitializeOneGUCOption(struct config_generic * gconf);
3284 static void push_old_value(struct config_generic * gconf, GucAction action);
3285 static void ReportGUCOption(struct config_generic * record);
3286 static void reapply_stacked_values(struct config_generic * variable,
3287                                            struct config_string *pHolder,
3288                                            GucStack *stack,
3289                                            const char *curvalue,
3290                                            GucContext curscontext, GucSource cursource);
3291 static void ShowGUCConfigOption(const char *name, DestReceiver *dest);
3292 static void ShowAllGUCConfig(DestReceiver *dest);
3293 static char *_ShowOption(struct config_generic * record, bool use_units);
3294 static bool validate_option_array_item(const char *name, const char *value,
3295                                                    bool skipIfNoPermissions);
3296
3297
3298 /*
3299  * Some infrastructure for checking malloc/strdup/realloc calls
3300  */
3301 static void *
3302 guc_malloc(int elevel, size_t size)
3303 {
3304         void       *data;
3305
3306         data = malloc(size);
3307         if (data == NULL)
3308                 ereport(elevel,
3309                                 (errcode(ERRCODE_OUT_OF_MEMORY),
3310                                  errmsg("out of memory")));
3311         return data;
3312 }
3313
3314 static void *
3315 guc_realloc(int elevel, void *old, size_t size)
3316 {
3317         void       *data;
3318
3319         data = realloc(old, size);
3320         if (data == NULL)
3321                 ereport(elevel,
3322                                 (errcode(ERRCODE_OUT_OF_MEMORY),
3323                                  errmsg("out of memory")));
3324         return data;
3325 }
3326
3327 static char *
3328 guc_strdup(int elevel, const char *src)
3329 {
3330         char       *data;
3331
3332         data = strdup(src);
3333         if (data == NULL)
3334                 ereport(elevel,
3335                                 (errcode(ERRCODE_OUT_OF_MEMORY),
3336                                  errmsg("out of memory")));
3337         return data;
3338 }
3339
3340
3341 /*
3342  * Detect whether strval is referenced anywhere in a GUC string item
3343  */
3344 static bool
3345 string_field_used(struct config_string * conf, char *strval)
3346 {
3347         GucStack   *stack;
3348
3349         if (strval == *(conf->variable) ||
3350                 strval == conf->reset_val ||
3351                 strval == conf->boot_val)
3352                 return true;
3353         for (stack = conf->gen.stack; stack; stack = stack->prev)
3354         {
3355                 if (strval == stack->prior.val.stringval ||
3356                         strval == stack->masked.val.stringval)
3357                         return true;
3358         }
3359         return false;
3360 }
3361
3362 /*
3363  * Support for assigning to a field of a string GUC item.  Free the prior
3364  * value if it's not referenced anywhere else in the item (including stacked
3365  * states).
3366  */
3367 static void
3368 set_string_field(struct config_string * conf, char **field, char *newval)
3369 {
3370         char       *oldval = *field;
3371
3372         /* Do the assignment */
3373         *field = newval;
3374
3375         /* Free old value if it's not NULL and isn't referenced anymore */
3376         if (oldval && !string_field_used(conf, oldval))
3377                 free(oldval);
3378 }
3379
3380 /*
3381  * Detect whether an "extra" struct is referenced anywhere in a GUC item
3382  */
3383 static bool
3384 extra_field_used(struct config_generic * gconf, void *extra)
3385 {
3386         GucStack   *stack;
3387
3388         if (extra == gconf->extra)
3389                 return true;
3390         switch (gconf->vartype)
3391         {
3392                 case PGC_BOOL:
3393                         if (extra == ((struct config_bool *) gconf)->reset_extra)
3394                                 return true;
3395                         break;
3396                 case PGC_INT:
3397                         if (extra == ((struct config_int *) gconf)->reset_extra)
3398                                 return true;
3399                         break;
3400                 case PGC_REAL:
3401                         if (extra == ((struct config_real *) gconf)->reset_extra)
3402                                 return true;
3403                         break;
3404                 case PGC_STRING:
3405                         if (extra == ((struct config_string *) gconf)->reset_extra)
3406                                 return true;
3407                         break;
3408                 case PGC_ENUM:
3409                         if (extra == ((struct config_enum *) gconf)->reset_extra)
3410                                 return true;
3411                         break;
3412         }
3413         for (stack = gconf->stack; stack; stack = stack->prev)
3414         {
3415                 if (extra == stack->prior.extra ||
3416                         extra == stack->masked.extra)
3417                         return true;
3418         }
3419
3420         return false;
3421 }
3422
3423 /*
3424  * Support for assigning to an "extra" field of a GUC item.  Free the prior
3425  * value if it's not referenced anywhere else in the item (including stacked
3426  * states).
3427  */
3428 static void
3429 set_extra_field(struct config_generic * gconf, void **field, void *newval)
3430 {
3431         void       *oldval = *field;
3432
3433         /* Do the assignment */
3434         *field = newval;
3435
3436         /* Free old value if it's not NULL and isn't referenced anymore */
3437         if (oldval && !extra_field_used(gconf, oldval))
3438                 free(oldval);
3439 }
3440
3441 /*
3442  * Support for copying a variable's active value into a stack entry.
3443  * The "extra" field associated with the active value is copied, too.
3444  *
3445  * NB: be sure stringval and extra fields of a new stack entry are
3446  * initialized to NULL before this is used, else we'll try to free() them.
3447  */
3448 static void
3449 set_stack_value(struct config_generic * gconf, config_var_value *val)
3450 {
3451         switch (gconf->vartype)
3452         {
3453                 case PGC_BOOL:
3454                         val->val.boolval =
3455                                 *((struct config_bool *) gconf)->variable;
3456                         break;
3457                 case PGC_INT:
3458                         val->val.intval =
3459                                 *((struct config_int *) gconf)->variable;
3460                         break;
3461                 case PGC_REAL:
3462                         val->val.realval =
3463                                 *((struct config_real *) gconf)->variable;
3464                         break;
3465                 case PGC_STRING:
3466                         set_string_field((struct config_string *) gconf,
3467                                                          &(val->val.stringval),
3468                                                          *((struct config_string *) gconf)->variable);
3469                         break;
3470                 case PGC_ENUM:
3471                         val->val.enumval =
3472                                 *((struct config_enum *) gconf)->variable;
3473                         break;
3474         }
3475         set_extra_field(gconf, &(val->extra), gconf->extra);
3476 }
3477
3478 /*
3479  * Support for discarding a no-longer-needed value in a stack entry.
3480  * The "extra" field associated with the stack entry is cleared, too.
3481  */
3482 static void
3483 discard_stack_value(struct config_generic * gconf, config_var_value *val)
3484 {
3485         switch (gconf->vartype)
3486         {
3487                 case PGC_BOOL:
3488                 case PGC_INT:
3489                 case PGC_REAL:
3490                 case PGC_ENUM:
3491                         /* no need to do anything */
3492                         break;
3493                 case PGC_STRING:
3494                         set_string_field((struct config_string *) gconf,
3495                                                          &(val->val.stringval),
3496                                                          NULL);
3497                         break;
3498         }
3499         set_extra_field(gconf, &(val->extra), NULL);
3500 }
3501
3502
3503 /*
3504  * Fetch the sorted array pointer (exported for help_config.c's use ONLY)
3505  */
3506 struct config_generic **
3507 get_guc_variables(void)
3508 {
3509         return guc_variables;
3510 }
3511
3512
3513 /*
3514  * Build the sorted array.      This is split out so that it could be
3515  * re-executed after startup (eg, we could allow loadable modules to
3516  * add vars, and then we'd need to re-sort).
3517  */
3518 void
3519 build_guc_variables(void)
3520 {
3521         int                     size_vars;
3522         int                     num_vars = 0;
3523         struct config_generic **guc_vars;
3524         int                     i;
3525
3526         for (i = 0; ConfigureNamesBool[i].gen.name; i++)
3527         {
3528                 struct config_bool *conf = &ConfigureNamesBool[i];
3529
3530                 /* Rather than requiring vartype to be filled in by hand, do this: */
3531                 conf->gen.vartype = PGC_BOOL;
3532                 num_vars++;
3533         }
3534
3535         for (i = 0; ConfigureNamesInt[i].gen.name; i++)
3536         {
3537                 struct config_int *conf = &ConfigureNamesInt[i];
3538
3539                 conf->gen.vartype = PGC_INT;
3540                 num_vars++;
3541         }
3542
3543         for (i = 0; ConfigureNamesReal[i].gen.name; i++)
3544         {
3545                 struct config_real *conf = &ConfigureNamesReal[i];
3546
3547                 conf->gen.vartype = PGC_REAL;
3548                 num_vars++;
3549         }
3550
3551         for (i = 0; ConfigureNamesString[i].gen.name; i++)
3552         {
3553                 struct config_string *conf = &ConfigureNamesString[i];
3554
3555                 conf->gen.vartype = PGC_STRING;
3556                 num_vars++;
3557         }
3558
3559         for (i = 0; ConfigureNamesEnum[i].gen.name; i++)
3560         {
3561                 struct config_enum *conf = &ConfigureNamesEnum[i];
3562
3563                 conf->gen.vartype = PGC_ENUM;
3564                 num_vars++;
3565         }
3566
3567         /*
3568          * Create table with 20% slack
3569          */
3570         size_vars = num_vars + num_vars / 4;
3571
3572         guc_vars = (struct config_generic **)
3573                 guc_malloc(FATAL, size_vars * sizeof(struct config_generic *));
3574
3575         num_vars = 0;
3576
3577         for (i = 0; ConfigureNamesBool[i].gen.name; i++)
3578                 guc_vars[num_vars++] = &ConfigureNamesBool[i].gen;
3579
3580         for (i = 0; ConfigureNamesInt[i].gen.name; i++)
3581                 guc_vars[num_vars++] = &ConfigureNamesInt[i].gen;
3582
3583         for (i = 0; ConfigureNamesReal[i].gen.name; i++)
3584                 guc_vars[num_vars++] = &ConfigureNamesReal[i].gen;
3585
3586         for (i = 0; ConfigureNamesString[i].gen.name; i++)
3587                 guc_vars[num_vars++] = &ConfigureNamesString[i].gen;
3588
3589         for (i = 0; ConfigureNamesEnum[i].gen.name; i++)
3590                 guc_vars[num_vars++] = &ConfigureNamesEnum[i].gen;
3591
3592         if (guc_variables)
3593                 free(guc_variables);
3594         guc_variables = guc_vars;
3595         num_guc_variables = num_vars;
3596         size_guc_variables = size_vars;
3597         qsort((void *) guc_variables, num_guc_variables,
3598                   sizeof(struct config_generic *), guc_var_compare);
3599 }
3600
3601 /*
3602  * Add a new GUC variable to the list of known variables. The
3603  * list is expanded if needed.
3604  */
3605 static bool
3606 add_guc_variable(struct config_generic * var, int elevel)
3607 {
3608         if (num_guc_variables + 1 >= size_guc_variables)
3609         {
3610                 /*
3611                  * Increase the vector by 25%
3612                  */
3613                 int                     size_vars = size_guc_variables + size_guc_variables / 4;
3614                 struct config_generic **guc_vars;
3615
3616                 if (size_vars == 0)
3617                 {
3618                         size_vars = 100;
3619                         guc_vars = (struct config_generic **)
3620                                 guc_malloc(elevel, size_vars * sizeof(struct config_generic *));
3621                 }
3622                 else
3623                 {
3624                         guc_vars = (struct config_generic **)
3625                                 guc_realloc(elevel, guc_variables, size_vars * sizeof(struct config_generic *));
3626                 }
3627
3628                 if (guc_vars == NULL)
3629                         return false;           /* out of memory */
3630
3631                 guc_variables = guc_vars;
3632                 size_guc_variables = size_vars;
3633         }
3634         guc_variables[num_guc_variables++] = var;
3635         qsort((void *) guc_variables, num_guc_variables,
3636                   sizeof(struct config_generic *), guc_var_compare);
3637         return true;
3638 }
3639
3640 /*
3641  * Create and add a placeholder variable for a custom variable name.
3642  */
3643 static struct config_generic *
3644 add_placeholder_variable(const char *name, int elevel)
3645 {
3646         size_t          sz = sizeof(struct config_string) + sizeof(char *);
3647         struct config_string *var;
3648         struct config_generic *gen;
3649
3650         var = (struct config_string *) guc_malloc(elevel, sz);
3651         if (var == NULL)
3652                 return NULL;
3653         memset(var, 0, sz);
3654         gen = &var->gen;
3655
3656         gen->name = guc_strdup(elevel, name);
3657         if (gen->name == NULL)
3658         {
3659                 free(var);
3660                 return NULL;
3661         }
3662
3663         gen->context = PGC_USERSET;
3664         gen->group = CUSTOM_OPTIONS;
3665         gen->short_desc = "GUC placeholder variable";
3666         gen->flags = GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE | GUC_CUSTOM_PLACEHOLDER;
3667         gen->vartype = PGC_STRING;
3668
3669         /*
3670          * The char* is allocated at the end of the struct since we have no
3671          * 'static' place to point to.  Note that the current value, as well as
3672          * the boot and reset values, start out NULL.
3673          */
3674         var->variable = (char **) (var + 1);
3675
3676         if (!add_guc_variable((struct config_generic *) var, elevel))
3677         {
3678                 free((void *) gen->name);
3679                 free(var);
3680                 return NULL;
3681         }
3682
3683         return gen;
3684 }
3685
3686 /*
3687  * Look up option NAME.  If it exists, return a pointer to its record,
3688  * else return NULL.  If create_placeholders is TRUE, we'll create a
3689  * placeholder record for a valid-looking custom variable name.
3690  */
3691 static struct config_generic *
3692 find_option(const char *name, bool create_placeholders, int elevel)
3693 {
3694         const char **key = &name;
3695         struct config_generic **res;
3696         int                     i;
3697
3698         Assert(name);
3699
3700         /*
3701          * By equating const char ** with struct config_generic *, we are assuming
3702          * the name field is first in config_generic.
3703          */
3704         res = (struct config_generic **) bsearch((void *) &key,
3705                                                                                          (void *) guc_variables,
3706                                                                                          num_guc_variables,
3707                                                                                          sizeof(struct config_generic *),
3708                                                                                          guc_var_compare);
3709         if (res)
3710                 return *res;
3711
3712         /*
3713          * See if the name is an obsolete name for a variable.  We assume that the
3714          * set of supported old names is short enough that a brute-force search is
3715          * the best way.
3716          */
3717         for (i = 0; map_old_guc_names[i] != NULL; i += 2)
3718         {
3719                 if (guc_name_compare(name, map_old_guc_names[i]) == 0)
3720                         return find_option(map_old_guc_names[i + 1], false, elevel);
3721         }
3722
3723         if (create_placeholders)
3724         {
3725                 /*
3726                  * Check if the name is qualified, and if so, add a placeholder.
3727                  */
3728                 if (strchr(name, GUC_QUALIFIER_SEPARATOR) != NULL)
3729                         return add_placeholder_variable(name, elevel);
3730         }
3731
3732         /* Unknown name */
3733         return NULL;
3734 }
3735
3736
3737 /*
3738  * comparator for qsorting and bsearching guc_variables array
3739  */
3740 static int
3741 guc_var_compare(const void *a, const void *b)
3742 {
3743         struct config_generic *confa = *(struct config_generic **) a;
3744         struct config_generic *confb = *(struct config_generic **) b;
3745
3746         return guc_name_compare(confa->name, confb->name);
3747 }
3748
3749 /*
3750  * the bare comparison function for GUC names
3751  */
3752 static int
3753 guc_name_compare(const char *namea, const char *nameb)
3754 {
3755         /*
3756          * The temptation to use strcasecmp() here must be resisted, because the
3757          * array ordering has to remain stable across setlocale() calls. So, build
3758          * our own with a simple ASCII-only downcasing.
3759          */
3760         while (*namea && *nameb)
3761         {
3762                 char            cha = *namea++;
3763                 char            chb = *nameb++;
3764
3765                 if (cha >= 'A' && cha <= 'Z')
3766                         cha += 'a' - 'A';
3767                 if (chb >= 'A' && chb <= 'Z')
3768                         chb += 'a' - 'A';
3769                 if (cha != chb)
3770                         return cha - chb;
3771         }
3772         if (*namea)
3773                 return 1;                               /* a is longer */
3774         if (*nameb)
3775                 return -1;                              /* b is longer */
3776         return 0;
3777 }
3778
3779
3780 /*
3781  * Initialize GUC options during program startup.
3782  *
3783  * Note that we cannot read the config file yet, since we have not yet
3784  * processed command-line switches.
3785  */
3786 void
3787 InitializeGUCOptions(void)
3788 {
3789         int                     i;
3790
3791         /*
3792          * Before log_line_prefix could possibly receive a nonempty setting, make
3793          * sure that timezone processing is minimally alive (see elog.c).
3794          */
3795         pg_timezone_initialize();
3796
3797         /*
3798          * Build sorted array of all GUC variables.
3799          */
3800         build_guc_variables();
3801
3802         /*
3803          * Load all variables with their compiled-in defaults, and initialize
3804          * status fields as needed.
3805          */
3806         for (i = 0; i < num_guc_variables; i++)
3807         {
3808                 InitializeOneGUCOption(guc_variables[i]);
3809         }
3810
3811         guc_dirty = false;
3812
3813         reporting_enabled = false;
3814
3815         /*
3816          * Prevent any attempt to override the transaction modes from
3817          * non-interactive sources.
3818          */
3819         SetConfigOption("transaction_isolation", "default",
3820                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3821         SetConfigOption("transaction_read_only", "no",
3822                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3823         SetConfigOption("transaction_deferrable", "no",
3824                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3825
3826         /*
3827          * For historical reasons, some GUC parameters can receive defaults from
3828          * environment variables.  Process those settings.
3829          */
3830         InitializeGUCOptionsFromEnvironment();
3831 }
3832
3833 /*
3834  * Assign any GUC values that can come from the server's environment.
3835  *
3836  * This is called from InitializeGUCOptions, and also from ProcessConfigFile
3837  * to deal with the possibility that a setting has been removed from
3838  * postgresql.conf and should now get a value from the environment.
3839  * (The latter is a kludge that should probably go away someday; if so,
3840  * fold this back into InitializeGUCOptions.)
3841  */
3842 static void
3843 InitializeGUCOptionsFromEnvironment(void)
3844 {
3845         char       *env;
3846         long            stack_rlimit;
3847
3848         env = getenv("PGPORT");
3849         if (env != NULL)
3850                 SetConfigOption("port", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3851
3852         env = getenv("PGDATESTYLE");
3853         if (env != NULL)
3854                 SetConfigOption("datestyle", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3855
3856         env = getenv("PGCLIENTENCODING");
3857         if (env != NULL)
3858                 SetConfigOption("client_encoding", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3859
3860         /*
3861          * rlimit isn't exactly an "environment variable", but it behaves about
3862          * the same.  If we can identify the platform stack depth rlimit, increase
3863          * default stack depth setting up to whatever is safe (but at most 2MB).
3864          */
3865         stack_rlimit = get_stack_depth_rlimit();
3866         if (stack_rlimit > 0)
3867         {
3868                 long            new_limit = (stack_rlimit - STACK_DEPTH_SLOP) / 1024L;
3869
3870                 if (new_limit > 100)
3871                 {
3872                         char            limbuf[16];
3873
3874                         new_limit = Min(new_limit, 2048);
3875                         sprintf(limbuf, "%ld", new_limit);
3876                         SetConfigOption("max_stack_depth", limbuf,
3877                                                         PGC_POSTMASTER, PGC_S_ENV_VAR);
3878                 }
3879         }
3880 }
3881
3882 /*
3883  * Initialize one GUC option variable to its compiled-in default.
3884  *
3885  * Note: the reason for calling check_hooks is not that we think the boot_val
3886  * might fail, but that the hooks might wish to compute an "extra" struct.
3887  */
3888 static void
3889 InitializeOneGUCOption(struct config_generic * gconf)
3890 {
3891         gconf->status = 0;
3892         gconf->source = PGC_S_DEFAULT;
3893         gconf->reset_source = PGC_S_DEFAULT;
3894         gconf->scontext = PGC_INTERNAL;
3895         gconf->reset_scontext = PGC_INTERNAL;
3896         gconf->stack = NULL;
3897         gconf->extra = NULL;
3898         gconf->sourcefile = NULL;
3899         gconf->sourceline = 0;
3900
3901         switch (gconf->vartype)
3902         {
3903                 case PGC_BOOL:
3904                         {
3905                                 struct config_bool *conf = (struct config_bool *) gconf;
3906                                 bool            newval = conf->boot_val;
3907                                 void       *extra = NULL;
3908
3909                                 if (!call_bool_check_hook(conf, &newval, &extra,
3910                                                                                   PGC_S_DEFAULT, LOG))
3911                                         elog(FATAL, "failed to initialize %s to %d",
3912                                                  conf->gen.name, (int) newval);
3913                                 if (conf->assign_hook)
3914                                         (*conf->assign_hook) (newval, extra);
3915                                 *conf->variable = conf->reset_val = newval;
3916                                 conf->gen.extra = conf->reset_extra = extra;
3917                                 break;
3918                         }
3919                 case PGC_INT:
3920                         {
3921                                 struct config_int *conf = (struct config_int *) gconf;
3922                                 int                     newval = conf->boot_val;
3923                                 void       *extra = NULL;
3924
3925                                 Assert(newval >= conf->min);
3926                                 Assert(newval <= conf->max);
3927                                 if (!call_int_check_hook(conf, &newval, &extra,
3928                                                                                  PGC_S_DEFAULT, LOG))
3929                                         elog(FATAL, "failed to initialize %s to %d",
3930                                                  conf->gen.name, newval);
3931                                 if (conf->assign_hook)
3932                                         (*conf->assign_hook) (newval, extra);
3933                                 *conf->variable = conf->reset_val = newval;
3934                                 conf->gen.extra = conf->reset_extra = extra;
3935                                 break;
3936                         }
3937                 case PGC_REAL:
3938                         {
3939                                 struct config_real *conf = (struct config_real *) gconf;
3940                                 double          newval = conf->boot_val;
3941                                 void       *extra = NULL;
3942
3943                                 Assert(newval >= conf->min);
3944                                 Assert(newval <= conf->max);
3945                                 if (!call_real_check_hook(conf, &newval, &extra,
3946                                                                                   PGC_S_DEFAULT, LOG))
3947                                         elog(FATAL, "failed to initialize %s to %g",
3948                                                  conf->gen.name, newval);
3949                                 if (conf->assign_hook)
3950                                         (*conf->assign_hook) (newval, extra);
3951                                 *conf->variable = conf->reset_val = newval;
3952                                 conf->gen.extra = conf->reset_extra = extra;
3953                                 break;
3954                         }
3955                 case PGC_STRING:
3956                         {
3957                                 struct config_string *conf = (struct config_string *) gconf;
3958                                 char       *newval;
3959                                 void       *extra = NULL;
3960
3961                                 /* non-NULL boot_val must always get strdup'd */
3962                                 if (conf->boot_val != NULL)
3963                                         newval = guc_strdup(FATAL, conf->boot_val);
3964                                 else
3965                                         newval = NULL;
3966
3967                                 if (!call_string_check_hook(conf, &newval, &extra,
3968                                                                                         PGC_S_DEFAULT, LOG))
3969                                         elog(FATAL, "failed to initialize %s to \"%s\"",
3970                                                  conf->gen.name, newval ? newval : "");
3971                                 if (conf->assign_hook)
3972                                         (*conf->assign_hook) (newval, extra);
3973                                 *conf->variable = conf->reset_val = newval;
3974                                 conf->gen.extra = conf->reset_extra = extra;
3975                                 break;
3976                         }
3977                 case PGC_ENUM:
3978                         {
3979                                 struct config_enum *conf = (struct config_enum *) gconf;
3980                                 int                     newval = conf->boot_val;
3981                                 void       *extra = NULL;
3982
3983                                 if (!call_enum_check_hook(conf, &newval, &extra,
3984                                                                                   PGC_S_DEFAULT, LOG))
3985                                         elog(FATAL, "failed to initialize %s to %d",
3986                                                  conf->gen.name, newval);
3987                                 if (conf->assign_hook)
3988                                         (*conf->assign_hook) (newval, extra);
3989                                 *conf->variable = conf->reset_val = newval;
3990                                 conf->gen.extra = conf->reset_extra = extra;
3991                                 break;
3992                         }
3993         }
3994 }
3995
3996
3997 /*
3998  * Select the configuration files and data directory to be used, and
3999  * do the initial read of postgresql.conf.
4000  *
4001  * This is called after processing command-line switches.
4002  *              userDoption is the -D switch value if any (NULL if unspecified).
4003  *              progname is just for use in error messages.
4004  *
4005  * Returns true on success; on failure, prints a suitable error message
4006  * to stderr and returns false.
4007  */
4008 bool
4009 SelectConfigFiles(const char *userDoption, const char *progname)
4010 {
4011         char       *configdir;
4012         char       *fname;
4013         struct stat stat_buf;
4014
4015         /* configdir is -D option, or $PGDATA if no -D */
4016         if (userDoption)
4017                 configdir = make_absolute_path(userDoption);
4018         else
4019                 configdir = make_absolute_path(getenv("PGDATA"));
4020
4021         /*
4022          * Find the configuration file: if config_file was specified on the
4023          * command line, use it, else use configdir/postgresql.conf.  In any case
4024          * ensure the result is an absolute path, so that it will be interpreted
4025          * the same way by future backends.
4026          */
4027         if (ConfigFileName)
4028                 fname = make_absolute_path(ConfigFileName);
4029         else if (configdir)
4030         {
4031                 fname = guc_malloc(FATAL,
4032                                                    strlen(configdir) + strlen(CONFIG_FILENAME) + 2);
4033                 sprintf(fname, "%s/%s", configdir, CONFIG_FILENAME);
4034         }
4035         else
4036         {
4037                 write_stderr("%s does not know where to find the server configuration file.\n"
4038                                          "You must specify the --config-file or -D invocation "
4039                                          "option or set the PGDATA environment variable.\n",
4040                                          progname);
4041                 return false;
4042         }
4043
4044         /*
4045          * Set the ConfigFileName GUC variable to its final value, ensuring that
4046          * it can't be overridden later.
4047          */
4048         SetConfigOption("config_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
4049         free(fname);
4050
4051         /*
4052          * Now read the config file for the first time.
4053          */
4054         if (stat(ConfigFileName, &stat_buf) != 0)
4055         {
4056                 write_stderr("%s cannot access the server configuration file \"%s\": %s\n",
4057                                          progname, ConfigFileName, strerror(errno));
4058                 return false;
4059         }
4060
4061         ProcessConfigFile(PGC_POSTMASTER);
4062
4063         /*
4064          * If the data_directory GUC variable has been set, use that as DataDir;
4065          * otherwise use configdir if set; else punt.
4066          *
4067          * Note: SetDataDir will copy and absolute-ize its argument, so we don't
4068          * have to.
4069          */
4070         if (data_directory)
4071                 SetDataDir(data_directory);
4072         else if (configdir)
4073                 SetDataDir(configdir);
4074         else
4075         {
4076                 write_stderr("%s does not know where to find the database system data.\n"
4077                                          "This can be specified as \"data_directory\" in \"%s\", "
4078                                          "or by the -D invocation option, or by the "
4079                                          "PGDATA environment variable.\n",
4080                                          progname, ConfigFileName);
4081                 return false;
4082         }
4083
4084         /*
4085          * Reflect the final DataDir value back into the data_directory GUC var.
4086          * (If you are wondering why we don't just make them a single variable,
4087          * it's because the EXEC_BACKEND case needs DataDir to be transmitted to
4088          * child backends specially.  XXX is that still true?  Given that we now
4089          * chdir to DataDir, EXEC_BACKEND can read the config file without knowing
4090          * DataDir in advance.)
4091          */
4092         SetConfigOption("data_directory", DataDir, PGC_POSTMASTER, PGC_S_OVERRIDE);
4093
4094         /*
4095          * If timezone_abbreviations wasn't set in the configuration file, install
4096          * the default value.  We do it this way because we can't safely install
4097          * a "real" value until my_exec_path is set, which may not have happened
4098          * when InitializeGUCOptions runs, so the bootstrap default value cannot
4099          * be the real desired default.
4100          */
4101         pg_timezone_abbrev_initialize();
4102
4103         /*
4104          * Figure out where pg_hba.conf is, and make sure the path is absolute.
4105          */
4106         if (HbaFileName)
4107                 fname = make_absolute_path(HbaFileName);
4108         else if (configdir)
4109         {
4110                 fname = guc_malloc(FATAL,
4111                                                    strlen(configdir) + strlen(HBA_FILENAME) + 2);
4112                 sprintf(fname, "%s/%s", configdir, HBA_FILENAME);
4113         }
4114         else
4115         {
4116                 write_stderr("%s does not know where to find the \"hba\" configuration file.\n"
4117                                          "This can be specified as \"hba_file\" in \"%s\", "
4118                                          "or by the -D invocation option, or by the "
4119                                          "PGDATA environment variable.\n",
4120                                          progname, ConfigFileName);
4121                 return false;
4122         }
4123         SetConfigOption("hba_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
4124         free(fname);
4125
4126         /*
4127          * Likewise for pg_ident.conf.
4128          */
4129         if (IdentFileName)
4130                 fname = make_absolute_path(IdentFileName);
4131         else if (configdir)
4132         {
4133                 fname = guc_malloc(FATAL,
4134                                                    strlen(configdir) + strlen(IDENT_FILENAME) + 2);
4135                 sprintf(fname, "%s/%s", configdir, IDENT_FILENAME);
4136         }
4137         else
4138         {
4139                 write_stderr("%s does not know where to find the \"ident\" configuration file.\n"
4140                                          "This can be specified as \"ident_file\" in \"%s\", "
4141                                          "or by the -D invocation option, or by the "
4142                                          "PGDATA environment variable.\n",
4143                                          progname, ConfigFileName);
4144                 return false;
4145         }
4146         SetConfigOption("ident_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
4147         free(fname);
4148
4149         free(configdir);
4150
4151         return true;
4152 }
4153
4154
4155 /*
4156  * Reset all options to their saved default values (implements RESET ALL)
4157  */
4158 void
4159 ResetAllOptions(void)
4160 {
4161         int                     i;
4162
4163         for (i = 0; i < num_guc_variables; i++)
4164         {
4165                 struct config_generic *gconf = guc_variables[i];
4166
4167                 /* Don't reset non-SET-able values */
4168                 if (gconf->context != PGC_SUSET &&
4169                         gconf->context != PGC_USERSET)
4170                         continue;
4171                 /* Don't reset if special exclusion from RESET ALL */
4172                 if (gconf->flags & GUC_NO_RESET_ALL)
4173                         continue;
4174                 /* No need to reset if wasn't SET */
4175                 if (gconf->source <= PGC_S_OVERRIDE)
4176                         continue;
4177
4178                 /* Save old value to support transaction abort */
4179                 push_old_value(gconf, GUC_ACTION_SET);
4180
4181                 switch (gconf->vartype)
4182                 {
4183                         case PGC_BOOL:
4184                                 {
4185                                         struct config_bool *conf = (struct config_bool *) gconf;
4186
4187                                         if (conf->assign_hook)
4188                                                 (*conf->assign_hook) (conf->reset_val,
4189                                                                                           conf->reset_extra);
4190                                         *conf->variable = conf->reset_val;
4191                                         set_extra_field(&conf->gen, &conf->gen.extra,
4192                                                                         conf->reset_extra);
4193                                         break;
4194                                 }
4195                         case PGC_INT:
4196                                 {
4197                                         struct config_int *conf = (struct config_int *) gconf;
4198
4199                                         if (conf->assign_hook)
4200                                                 (*conf->assign_hook) (conf->reset_val,
4201                                                                                           conf->reset_extra);
4202                                         *conf->variable = conf->reset_val;
4203                                         set_extra_field(&conf->gen, &conf->gen.extra,
4204                                                                         conf->reset_extra);
4205                                         break;
4206                                 }
4207                         case PGC_REAL:
4208                                 {
4209                                         struct config_real *conf = (struct config_real *) gconf;
4210
4211                                         if (conf->assign_hook)
4212                                                 (*conf->assign_hook) (conf->reset_val,
4213                                                                                           conf->reset_extra);
4214                                         *conf->variable = conf->reset_val;
4215                                         set_extra_field(&conf->gen, &conf->gen.extra,
4216                                                                         conf->reset_extra);
4217                                         break;
4218                                 }
4219                         case PGC_STRING:
4220                                 {
4221                                         struct config_string *conf = (struct config_string *) gconf;
4222
4223                                         if (conf->assign_hook)
4224                                                 (*conf->assign_hook) (conf->reset_val,
4225                                                                                           conf->reset_extra);
4226                                         set_string_field(conf, conf->variable, conf->reset_val);
4227                                         set_extra_field(&conf->gen, &conf->gen.extra,
4228                                                                         conf->reset_extra);
4229                                         break;
4230                                 }
4231                         case PGC_ENUM:
4232                                 {
4233                                         struct config_enum *conf = (struct config_enum *) gconf;
4234
4235                                         if (conf->assign_hook)
4236                                                 (*conf->assign_hook) (conf->reset_val,
4237                                                                                           conf->reset_extra);
4238                                         *conf->variable = conf->reset_val;
4239                                         set_extra_field(&conf->gen, &conf->gen.extra,
4240                                                                         conf->reset_extra);
4241                                         break;
4242                                 }
4243                 }
4244
4245                 gconf->source = gconf->reset_source;
4246                 gconf->scontext = gconf->reset_scontext;
4247
4248                 if (gconf->flags & GUC_REPORT)
4249                         ReportGUCOption(gconf);
4250         }
4251 }
4252
4253
4254 /*
4255  * push_old_value
4256  *              Push previous state during transactional assignment to a GUC variable.
4257  */
4258 static void
4259 push_old_value(struct config_generic * gconf, GucAction action)
4260 {
4261         GucStack   *stack;
4262
4263         /* If we're not inside a nest level, do nothing */
4264         if (GUCNestLevel == 0)
4265                 return;
4266
4267         /* Do we already have a stack entry of the current nest level? */
4268         stack = gconf->stack;
4269         if (stack && stack->nest_level >= GUCNestLevel)
4270         {
4271                 /* Yes, so adjust its state if necessary */
4272                 Assert(stack->nest_level == GUCNestLevel);
4273                 switch (action)
4274                 {
4275                         case GUC_ACTION_SET:
4276                                 /* SET overrides any prior action at same nest level */
4277                                 if (stack->state == GUC_SET_LOCAL)
4278                                 {
4279                                         /* must discard old masked value */
4280                                         discard_stack_value(gconf, &stack->masked);
4281                                 }
4282                                 stack->state = GUC_SET;
4283                                 break;
4284                         case GUC_ACTION_LOCAL:
4285                                 if (stack->state == GUC_SET)
4286                                 {
4287                                         /* SET followed by SET LOCAL, remember SET's value */
4288                                         stack->masked_scontext = gconf->scontext;
4289                                         set_stack_value(gconf, &stack->masked);
4290                                         stack->state = GUC_SET_LOCAL;
4291                                 }
4292                                 /* in all other cases, no change to stack entry */
4293                                 break;
4294                         case GUC_ACTION_SAVE:
4295                                 /* Could only have a prior SAVE of same variable */
4296                                 Assert(stack->state == GUC_SAVE);
4297                                 break;
4298                 }
4299                 Assert(guc_dirty);              /* must be set already */
4300                 return;
4301         }
4302
4303         /*
4304          * Push a new stack entry
4305          *
4306          * We keep all the stack entries in TopTransactionContext for simplicity.
4307          */
4308         stack = (GucStack *) MemoryContextAllocZero(TopTransactionContext,
4309                                                                                                 sizeof(GucStack));
4310
4311         stack->prev = gconf->stack;
4312         stack->nest_level = GUCNestLevel;
4313         switch (action)
4314         {
4315                 case GUC_ACTION_SET:
4316                         stack->state = GUC_SET;
4317                         break;
4318                 case GUC_ACTION_LOCAL:
4319                         stack->state = GUC_LOCAL;
4320                         break;
4321                 case GUC_ACTION_SAVE:
4322                         stack->state = GUC_SAVE;
4323                         break;
4324         }
4325         stack->source = gconf->source;
4326         stack->scontext = gconf->scontext;
4327         set_stack_value(gconf, &stack->prior);
4328
4329         gconf->stack = stack;
4330
4331         /* Ensure we remember to pop at end of xact */
4332         guc_dirty = true;
4333 }
4334
4335
4336 /*
4337  * Do GUC processing at main transaction start.
4338  */
4339 void
4340 AtStart_GUC(void)
4341 {
4342         /*
4343          * The nest level should be 0 between transactions; if it isn't, somebody
4344          * didn't call AtEOXact_GUC, or called it with the wrong nestLevel.  We
4345          * throw a warning but make no other effort to clean up.
4346          */
4347         if (GUCNestLevel != 0)
4348                 elog(WARNING, "GUC nest level = %d at transaction start",
4349                          GUCNestLevel);
4350         GUCNestLevel = 1;
4351 }
4352
4353 /*
4354  * Enter a new nesting level for GUC values.  This is called at subtransaction
4355  * start, and when entering a function that has proconfig settings, and in
4356  * some other places where we want to set GUC variables transiently.
4357  * NOTE we must not risk error here, else subtransaction start will be unhappy.
4358  */
4359 int
4360 NewGUCNestLevel(void)
4361 {
4362         return ++GUCNestLevel;
4363 }
4364
4365 /*
4366  * Do GUC processing at transaction or subtransaction commit or abort, or
4367  * when exiting a function that has proconfig settings, or when undoing a
4368  * transient assignment to some GUC variables.  (The name is thus a bit of
4369  * a misnomer; perhaps it should be ExitGUCNestLevel or some such.)
4370  * During abort, we discard all GUC settings that were applied at nesting
4371  * levels >= nestLevel.  nestLevel == 1 corresponds to the main transaction.
4372  */
4373 void
4374 AtEOXact_GUC(bool isCommit, int nestLevel)
4375 {
4376         bool            still_dirty;
4377         int                     i;
4378
4379         /*
4380          * Note: it's possible to get here with GUCNestLevel == nestLevel-1 during
4381          * abort, if there is a failure during transaction start before
4382          * AtStart_GUC is called.
4383          */
4384         Assert(nestLevel > 0 &&
4385                    (nestLevel <= GUCNestLevel ||
4386                         (nestLevel == GUCNestLevel + 1 && !isCommit)));
4387
4388         /* Quick exit if nothing's changed in this transaction */
4389         if (!guc_dirty)
4390         {
4391                 GUCNestLevel = nestLevel - 1;
4392                 return;
4393         }
4394
4395         still_dirty = false;
4396         for (i = 0; i < num_guc_variables; i++)
4397         {
4398                 struct config_generic *gconf = guc_variables[i];
4399                 GucStack   *stack;
4400
4401                 /*
4402                  * Process and pop each stack entry within the nest level. To simplify
4403                  * fmgr_security_definer() and other places that use GUC_ACTION_SAVE,
4404                  * we allow failure exit from code that uses a local nest level to be
4405                  * recovered at the surrounding transaction or subtransaction abort;
4406                  * so there could be more than one stack entry to pop.
4407                  */
4408                 while ((stack = gconf->stack) != NULL &&
4409                            stack->nest_level >= nestLevel)
4410                 {
4411                         GucStack   *prev = stack->prev;
4412                         bool            restorePrior = false;
4413                         bool            restoreMasked = false;
4414                         bool            changed;
4415
4416                         /*
4417                          * In this next bit, if we don't set either restorePrior or
4418                          * restoreMasked, we must "discard" any unwanted fields of the
4419                          * stack entries to avoid leaking memory.  If we do set one of
4420                          * those flags, unused fields will be cleaned up after restoring.
4421                          */
4422                         if (!isCommit)          /* if abort, always restore prior value */
4423                                 restorePrior = true;
4424                         else if (stack->state == GUC_SAVE)
4425                                 restorePrior = true;
4426                         else if (stack->nest_level == 1)
4427                         {
4428                                 /* transaction commit */
4429                                 if (stack->state == GUC_SET_LOCAL)
4430                                         restoreMasked = true;
4431                                 else if (stack->state == GUC_SET)
4432                                 {
4433                                         /* we keep the current active value */
4434                                         discard_stack_value(gconf, &stack->prior);
4435                                 }
4436                                 else    /* must be GUC_LOCAL */
4437                                         restorePrior = true;
4438                         }
4439                         else if (prev == NULL ||
4440                                          prev->nest_level < stack->nest_level - 1)
4441                         {
4442                                 /* decrement entry's level and do not pop it */
4443                                 stack->nest_level--;
4444                                 continue;
4445                         }
4446                         else
4447                         {
4448                                 /*
4449                                  * We have to merge this stack entry into prev. See README for
4450                                  * discussion of this bit.
4451                                  */
4452                                 switch (stack->state)
4453                                 {
4454                                         case GUC_SAVE:
4455                                                 Assert(false);  /* can't get here */
4456
4457                                         case GUC_SET:
4458                                                 /* next level always becomes SET */
4459                                                 discard_stack_value(gconf, &stack->prior);
4460                                                 if (prev->state == GUC_SET_LOCAL)
4461                                                         discard_stack_value(gconf, &prev->masked);
4462                                                 prev->state = GUC_SET;
4463                                                 break;
4464
4465                                         case GUC_LOCAL:
4466                                                 if (prev->state == GUC_SET)
4467                                                 {
4468                                                         /* LOCAL migrates down */
4469                                                         prev->masked_scontext = stack->scontext;
4470                                                         prev->masked = stack->prior;
4471                                                         prev->state = GUC_SET_LOCAL;
4472                                                 }
4473                                                 else
4474                                                 {
4475                                                         /* else just forget this stack level */
4476                                                         discard_stack_value(gconf, &stack->prior);
4477                                                 }
4478                                                 break;
4479
4480                                         case GUC_SET_LOCAL:
4481                                                 /* prior state at this level no longer wanted */
4482                                                 discard_stack_value(gconf, &stack->prior);
4483                                                 /* copy down the masked state */
4484                                                 prev->masked_scontext = stack->masked_scontext;
4485                                                 if (prev->state == GUC_SET_LOCAL)
4486                                                         discard_stack_value(gconf, &prev->masked);
4487                                                 prev->masked = stack->masked;
4488                                                 prev->state = GUC_SET_LOCAL;
4489                                                 break;
4490                                 }
4491                         }
4492
4493                         changed = false;
4494
4495                         if (restorePrior || restoreMasked)
4496                         {
4497                                 /* Perform appropriate restoration of the stacked value */
4498                                 config_var_value newvalue;
4499                                 GucSource       newsource;
4500                                 GucContext      newscontext;
4501
4502                                 if (restoreMasked)
4503                                 {
4504                                         newvalue = stack->masked;
4505                                         newsource = PGC_S_SESSION;
4506                                         newscontext = stack->masked_scontext;
4507                                 }
4508                                 else
4509                                 {
4510                                         newvalue = stack->prior;
4511                                         newsource = stack->source;
4512                                         newscontext = stack->scontext;
4513                                 }
4514
4515                                 switch (gconf->vartype)
4516                                 {
4517                                         case PGC_BOOL:
4518                                                 {
4519                                                         struct config_bool *conf = (struct config_bool *) gconf;
4520                                                         bool            newval = newvalue.val.boolval;
4521                                                         void       *newextra = newvalue.extra;
4522
4523                                                         if (*conf->variable != newval ||
4524                                                                 conf->gen.extra != newextra)
4525                                                         {
4526                                                                 if (conf->assign_hook)
4527                                                                         (*conf->assign_hook) (newval, newextra);
4528                                                                 *conf->variable = newval;
4529                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4530                                                                                                 newextra);
4531                                                                 changed = true;
4532                                                         }
4533                                                         break;
4534                                                 }
4535                                         case PGC_INT:
4536                                                 {
4537                                                         struct config_int *conf = (struct config_int *) gconf;
4538                                                         int                     newval = newvalue.val.intval;
4539                                                         void       *newextra = newvalue.extra;
4540
4541                                                         if (*conf->variable != newval ||
4542                                                                 conf->gen.extra != newextra)
4543                                                         {
4544                                                                 if (conf->assign_hook)
4545                                                                         (*conf->assign_hook) (newval, newextra);
4546                                                                 *conf->variable = newval;
4547                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4548                                                                                                 newextra);
4549                                                                 changed = true;
4550                                                         }
4551                                                         break;
4552                                                 }
4553                                         case PGC_REAL:
4554                                                 {
4555                                                         struct config_real *conf = (struct config_real *) gconf;
4556                                                         double          newval = newvalue.val.realval;
4557                                                         void       *newextra = newvalue.extra;
4558
4559                                                         if (*conf->variable != newval ||
4560                                                                 conf->gen.extra != newextra)
4561                                                         {
4562                                                                 if (conf->assign_hook)
4563                                                                         (*conf->assign_hook) (newval, newextra);
4564                                                                 *conf->variable = newval;
4565                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4566                                                                                                 newextra);
4567                                                                 changed = true;
4568                                                         }
4569                                                         break;
4570                                                 }
4571                                         case PGC_STRING:
4572                                                 {
4573                                                         struct config_string *conf = (struct config_string *) gconf;
4574                                                         char       *newval = newvalue.val.stringval;
4575                                                         void       *newextra = newvalue.extra;
4576
4577                                                         if (*conf->variable != newval ||
4578                                                                 conf->gen.extra != newextra)
4579                                                         {
4580                                                                 if (conf->assign_hook)
4581                                                                         (*conf->assign_hook) (newval, newextra);
4582                                                                 set_string_field(conf, conf->variable, newval);
4583                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4584                                                                                                 newextra);
4585                                                                 changed = true;
4586                                                         }
4587
4588                                                         /*
4589                                                          * Release stacked values if not used anymore. We
4590                                                          * could use discard_stack_value() here, but since
4591                                                          * we have type-specific code anyway, might as
4592                                                          * well inline it.
4593                                                          */
4594                                                         set_string_field(conf, &stack->prior.val.stringval, NULL);
4595                                                         set_string_field(conf, &stack->masked.val.stringval, NULL);
4596                                                         break;
4597                                                 }
4598                                         case PGC_ENUM:
4599                                                 {
4600                                                         struct config_enum *conf = (struct config_enum *) gconf;
4601                                                         int                     newval = newvalue.val.enumval;
4602                                                         void       *newextra = newvalue.extra;
4603
4604                                                         if (*conf->variable != newval ||
4605                                                                 conf->gen.extra != newextra)
4606                                                         {
4607                                                                 if (conf->assign_hook)
4608                                                                         (*conf->assign_hook) (newval, newextra);
4609                                                                 *conf->variable = newval;
4610                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4611                                                                                                 newextra);
4612                                                                 changed = true;
4613                                                         }
4614                                                         break;
4615                                                 }
4616                                 }
4617
4618                                 /*
4619                                  * Release stacked extra values if not used anymore.
4620                                  */
4621                                 set_extra_field(gconf, &(stack->prior.extra), NULL);
4622                                 set_extra_field(gconf, &(stack->masked.extra), NULL);
4623
4624                                 /* And restore source information */
4625                                 gconf->source = newsource;
4626                                 gconf->scontext = newscontext;
4627                         }
4628
4629                         /* Finish popping the state stack */
4630                         gconf->stack = prev;
4631                         pfree(stack);
4632
4633                         /* Report new value if we changed it */
4634                         if (changed && (gconf->flags & GUC_REPORT))
4635                                 ReportGUCOption(gconf);
4636                 }                                               /* end of stack-popping loop */
4637
4638                 if (stack != NULL)
4639                         still_dirty = true;
4640         }
4641
4642         /* If there are no remaining stack entries, we can reset guc_dirty */
4643         guc_dirty = still_dirty;
4644
4645         /* Update nesting level */
4646         GUCNestLevel = nestLevel - 1;
4647 }
4648
4649
4650 /*
4651  * Start up automatic reporting of changes to variables marked GUC_REPORT.
4652  * This is executed at completion of backend startup.
4653  */
4654 void
4655 BeginReportingGUCOptions(void)
4656 {
4657         int                     i;
4658
4659         /*
4660          * Don't do anything unless talking to an interactive frontend of protocol
4661          * 3.0 or later.
4662          */
4663         if (whereToSendOutput != DestRemote ||
4664                 PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
4665                 return;
4666
4667         reporting_enabled = true;
4668
4669         /* Transmit initial values of interesting variables */
4670         for (i = 0; i < num_guc_variables; i++)
4671         {
4672                 struct config_generic *conf = guc_variables[i];
4673
4674                 if (conf->flags & GUC_REPORT)
4675                         ReportGUCOption(conf);
4676         }
4677 }
4678
4679 /*
4680  * ReportGUCOption: if appropriate, transmit option value to frontend
4681  */
4682 static void
4683 ReportGUCOption(struct config_generic * record)
4684 {
4685         if (reporting_enabled && (record->flags & GUC_REPORT))
4686         {
4687                 char       *val = _ShowOption(record, false);
4688                 StringInfoData msgbuf;
4689
4690                 pq_beginmessage(&msgbuf, 'S');
4691                 pq_sendstring(&msgbuf, record->name);
4692                 pq_sendstring(&msgbuf, val);
4693                 pq_endmessage(&msgbuf);
4694
4695                 pfree(val);
4696         }
4697 }
4698
4699 /*
4700  * Try to parse value as an integer.  The accepted formats are the
4701  * usual decimal, octal, or hexadecimal formats, optionally followed by
4702  * a unit name if "flags" indicates a unit is allowed.
4703  *
4704  * If the string parses okay, return true, else false.
4705  * If okay and result is not NULL, return the value in *result.
4706  * If not okay and hintmsg is not NULL, *hintmsg is set to a suitable
4707  *      HINT message, or NULL if no hint provided.
4708  */
4709 bool
4710 parse_int(const char *value, int *result, int flags, const char **hintmsg)
4711 {
4712         int64           val;
4713         char       *endptr;
4714
4715         /* To suppress compiler warnings, always set output params */
4716         if (result)
4717                 *result = 0;
4718         if (hintmsg)
4719                 *hintmsg = NULL;
4720
4721         /* We assume here that int64 is at least as wide as long */
4722         errno = 0;
4723         val = strtol(value, &endptr, 0);
4724
4725         if (endptr == value)
4726                 return false;                   /* no HINT for integer syntax error */
4727
4728         if (errno == ERANGE || val != (int64) ((int32) val))
4729         {
4730                 if (hintmsg)
4731                         *hintmsg = gettext_noop("Value exceeds integer range.");
4732                 return false;
4733         }
4734
4735         /* allow whitespace between integer and unit */
4736         while (isspace((unsigned char) *endptr))
4737                 endptr++;
4738
4739         /* Handle possible unit */
4740         if (*endptr != '\0')
4741         {
4742                 /*
4743                  * Note: the multiple-switch coding technique here is a bit tedious,
4744                  * but seems necessary to avoid intermediate-value overflows.
4745                  */
4746                 if (flags & GUC_UNIT_MEMORY)
4747                 {
4748                         /* Set hint for use if no match or trailing garbage */
4749                         if (hintmsg)
4750                                 *hintmsg = gettext_noop("Valid units for this parameter are \"kB\", \"MB\", and \"GB\".");
4751
4752 #if BLCKSZ < 1024 || BLCKSZ > (1024*1024)
4753 #error BLCKSZ must be between 1KB and 1MB
4754 #endif
4755 #if XLOG_BLCKSZ < 1024 || XLOG_BLCKSZ > (1024*1024)
4756 #error XLOG_BLCKSZ must be between 1KB and 1MB
4757 #endif
4758
4759                         if (strncmp(endptr, "kB", 2) == 0)
4760                         {
4761                                 endptr += 2;
4762                                 switch (flags & GUC_UNIT_MEMORY)
4763                                 {
4764                                         case GUC_UNIT_BLOCKS:
4765                                                 val /= (BLCKSZ / 1024);
4766                                                 break;
4767                                         case GUC_UNIT_XBLOCKS:
4768                                                 val /= (XLOG_BLCKSZ / 1024);
4769                                                 break;
4770                                 }
4771                         }
4772                         else if (strncmp(endptr, "MB", 2) == 0)
4773                         {
4774                                 endptr += 2;
4775                                 switch (flags & GUC_UNIT_MEMORY)
4776                                 {
4777                                         case GUC_UNIT_KB:
4778                                                 val *= KB_PER_MB;
4779                                                 break;
4780                                         case GUC_UNIT_BLOCKS:
4781                                                 val *= KB_PER_MB / (BLCKSZ / 1024);
4782                                                 break;
4783                                         case GUC_UNIT_XBLOCKS:
4784                                                 val *= KB_PER_MB / (XLOG_BLCKSZ / 1024);
4785                                                 break;
4786                                 }
4787                         }
4788                         else if (strncmp(endptr, "GB", 2) == 0)
4789                         {
4790                                 endptr += 2;
4791                                 switch (flags & GUC_UNIT_MEMORY)
4792                                 {
4793                                         case GUC_UNIT_KB:
4794                                                 val *= KB_PER_GB;
4795                                                 break;
4796                                         case GUC_UNIT_BLOCKS:
4797                                                 val *= KB_PER_GB / (BLCKSZ / 1024);
4798                                                 break;
4799                                         case GUC_UNIT_XBLOCKS:
4800                                                 val *= KB_PER_GB / (XLOG_BLCKSZ / 1024);
4801                                                 break;
4802                                 }
4803                         }
4804                 }
4805                 else if (flags & GUC_UNIT_TIME)
4806                 {
4807                         /* Set hint for use if no match or trailing garbage */
4808                         if (hintmsg)
4809                                 *hintmsg = gettext_noop("Valid units for this parameter are \"ms\", \"s\", \"min\", \"h\", and \"d\".");
4810
4811                         if (strncmp(endptr, "ms", 2) == 0)
4812                         {
4813                                 endptr += 2;
4814                                 switch (flags & GUC_UNIT_TIME)
4815                                 {
4816                                         case GUC_UNIT_S:
4817                                                 val /= MS_PER_S;
4818                                                 break;
4819                                         case GUC_UNIT_MIN:
4820                                                 val /= MS_PER_MIN;
4821                                                 break;
4822                                 }
4823                         }
4824                         else if (strncmp(endptr, "s", 1) == 0)
4825                         {
4826                                 endptr += 1;
4827                                 switch (flags & GUC_UNIT_TIME)
4828                                 {
4829                                         case GUC_UNIT_MS:
4830                                                 val *= MS_PER_S;
4831                                                 break;
4832                                         case GUC_UNIT_MIN:
4833                                                 val /= S_PER_MIN;
4834                                                 break;
4835                                 }
4836                         }
4837                         else if (strncmp(endptr, "min", 3) == 0)
4838                         {
4839                                 endptr += 3;
4840                                 switch (flags & GUC_UNIT_TIME)
4841                                 {
4842                                         case GUC_UNIT_MS:
4843                                                 val *= MS_PER_MIN;
4844                                                 break;
4845                                         case GUC_UNIT_S:
4846                                                 val *= S_PER_MIN;
4847                                                 break;
4848                                 }
4849                         }
4850                         else if (strncmp(endptr, "h", 1) == 0)
4851                         {
4852                                 endptr += 1;
4853                                 switch (flags & GUC_UNIT_TIME)
4854                                 {
4855                                         case GUC_UNIT_MS:
4856                                                 val *= MS_PER_H;
4857                                                 break;
4858                                         case GUC_UNIT_S:
4859                                                 val *= S_PER_H;
4860                                                 break;
4861                                         case GUC_UNIT_MIN:
4862                                                 val *= MIN_PER_H;
4863                                                 break;
4864                                 }
4865                         }
4866                         else if (strncmp(endptr, "d", 1) == 0)
4867                         {
4868                                 endptr += 1;
4869                                 switch (flags & GUC_UNIT_TIME)
4870                                 {
4871                                         case GUC_UNIT_MS:
4872                                                 val *= MS_PER_D;
4873                                                 break;
4874                                         case GUC_UNIT_S:
4875                                                 val *= S_PER_D;
4876                                                 break;
4877                                         case GUC_UNIT_MIN:
4878                                                 val *= MIN_PER_D;
4879                                                 break;
4880                                 }
4881                         }
4882                 }
4883
4884                 /* allow whitespace after unit */
4885                 while (isspace((unsigned char) *endptr))
4886                         endptr++;
4887
4888                 if (*endptr != '\0')
4889                         return false;           /* appropriate hint, if any, already set */
4890
4891                 /* Check for overflow due to units conversion */
4892                 if (val != (int64) ((int32) val))
4893                 {
4894                         if (hintmsg)
4895                                 *hintmsg = gettext_noop("Value exceeds integer range.");
4896                         return false;
4897                 }
4898         }
4899
4900         if (result)
4901                 *result = (int) val;
4902         return true;
4903 }
4904
4905
4906
4907 /*
4908  * Try to parse value as a floating point number in the usual format.
4909  * If the string parses okay, return true, else false.
4910  * If okay and result is not NULL, return the value in *result.
4911  */
4912 bool
4913 parse_real(const char *value, double *result)
4914 {
4915         double          val;
4916         char       *endptr;
4917
4918         if (result)
4919                 *result = 0;                    /* suppress compiler warning */
4920
4921         errno = 0;
4922         val = strtod(value, &endptr);
4923         if (endptr == value || errno == ERANGE)
4924                 return false;
4925
4926         /* allow whitespace after number */
4927         while (isspace((unsigned char) *endptr))
4928                 endptr++;
4929         if (*endptr != '\0')
4930                 return false;
4931
4932         if (result)
4933                 *result = val;
4934         return true;
4935 }
4936
4937
4938 /*
4939  * Lookup the name for an enum option with the selected value.
4940  * Should only ever be called with known-valid values, so throws
4941  * an elog(ERROR) if the enum option is not found.
4942  *
4943  * The returned string is a pointer to static data and not
4944  * allocated for modification.
4945  */
4946 const char *
4947 config_enum_lookup_by_value(struct config_enum * record, int val)
4948 {
4949         const struct config_enum_entry *entry;
4950
4951         for (entry = record->options; entry && entry->name; entry++)
4952         {
4953                 if (entry->val == val)
4954                         return entry->name;
4955         }
4956
4957         elog(ERROR, "could not find enum option %d for %s",
4958                  val, record->gen.name);
4959         return NULL;                            /* silence compiler */
4960 }
4961
4962
4963 /*
4964  * Lookup the value for an enum option with the selected name
4965  * (case-insensitive).
4966  * If the enum option is found, sets the retval value and returns
4967  * true. If it's not found, return FALSE and retval is set to 0.
4968  */
4969 bool
4970 config_enum_lookup_by_name(struct config_enum * record, const char *value,
4971                                                    int *retval)
4972 {
4973         const struct config_enum_entry *entry;
4974
4975         for (entry = record->options; entry && entry->name; entry++)
4976         {
4977                 if (pg_strcasecmp(value, entry->name) == 0)
4978                 {
4979                         *retval = entry->val;
4980                         return TRUE;
4981                 }
4982         }
4983
4984         *retval = 0;
4985         return FALSE;
4986 }
4987
4988
4989 /*
4990  * Return a list of all available options for an enum, excluding
4991  * hidden ones, separated by the given separator.
4992  * If prefix is non-NULL, it is added before the first enum value.
4993  * If suffix is non-NULL, it is added to the end of the string.
4994  */
4995 static char *
4996 config_enum_get_options(struct config_enum * record, const char *prefix,
4997                                                 const char *suffix, const char *separator)
4998 {
4999         const struct config_enum_entry *entry;
5000         StringInfoData retstr;
5001         int                     seplen;
5002
5003         initStringInfo(&retstr);
5004         appendStringInfoString(&retstr, prefix);
5005
5006         seplen = strlen(separator);
5007         for (entry = record->options; entry && entry->name; entry++)
5008         {
5009                 if (!entry->hidden)
5010                 {
5011                         appendStringInfoString(&retstr, entry->name);
5012                         appendBinaryStringInfo(&retstr, separator, seplen);
5013                 }
5014         }
5015
5016         /*
5017          * All the entries may have been hidden, leaving the string empty if no
5018          * prefix was given. This indicates a broken GUC setup, since there is no
5019          * use for an enum without any values, so we just check to make sure we
5020          * don't write to invalid memory instead of actually trying to do
5021          * something smart with it.
5022          */
5023         if (retstr.len >= seplen)
5024         {
5025                 /* Replace final separator */
5026                 retstr.data[retstr.len - seplen] = '\0';
5027                 retstr.len -= seplen;
5028         }
5029
5030         appendStringInfoString(&retstr, suffix);
5031
5032         return retstr.data;
5033 }
5034
5035
5036 /*
5037  * Sets option `name' to given value.
5038  *
5039  * The value should be a string, which will be parsed and converted to
5040  * the appropriate data type.  The context and source parameters indicate
5041  * in which context this function is being called, so that it can apply the
5042  * access restrictions properly.
5043  *
5044  * If value is NULL, set the option to its default value (normally the
5045  * reset_val, but if source == PGC_S_DEFAULT we instead use the boot_val).
5046  *
5047  * action indicates whether to set the value globally in the session, locally
5048  * to the current top transaction, or just for the duration of a function call.
5049  *
5050  * If changeVal is false then don't really set the option but do all
5051  * the checks to see if it would work.
5052  *
5053  * elevel should normally be passed as zero, allowing this function to make
5054  * its standard choice of ereport level.  However some callers need to be
5055  * able to override that choice; they should pass the ereport level to use.
5056  *
5057  * Return value:
5058  *      +1: the value is valid and was successfully applied.
5059  *      0:  the name or value is invalid (but see below).
5060  *      -1: the value was not applied because of context, priority, or changeVal.
5061  *
5062  * If there is an error (non-existing option, invalid value) then an
5063  * ereport(ERROR) is thrown *unless* this is called for a source for which
5064  * we don't want an ERROR (currently, those are defaults, the config file,
5065  * and per-database or per-user settings, as well as callers who specify
5066  * a less-than-ERROR elevel).  In those cases we write a suitable error
5067  * message via ereport() and return 0.
5068  *
5069  * See also SetConfigOption for an external interface.
5070  */
5071 int
5072 set_config_option(const char *name, const char *value,
5073                                   GucContext context, GucSource source,
5074                                   GucAction action, bool changeVal, int elevel)
5075 {
5076         struct config_generic *record;
5077         bool            prohibitValueChange = false;
5078         bool            makeDefault;
5079
5080         if (elevel == 0)
5081         {
5082                 if (source == PGC_S_DEFAULT || source == PGC_S_FILE)
5083                 {
5084                         /*
5085                          * To avoid cluttering the log, only the postmaster bleats loudly
5086                          * about problems with the config file.
5087                          */
5088                         elevel = IsUnderPostmaster ? DEBUG3 : LOG;
5089                 }
5090                 else if (source == PGC_S_DATABASE || source == PGC_S_USER ||
5091                                  source == PGC_S_DATABASE_USER)
5092                         elevel = WARNING;
5093                 else
5094                         elevel = ERROR;
5095         }
5096
5097         record = find_option(name, true, elevel);
5098         if (record == NULL)
5099         {
5100                 ereport(elevel,
5101                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
5102                            errmsg("unrecognized configuration parameter \"%s\"", name)));
5103                 return 0;
5104         }
5105
5106         /*
5107          * Check if the option can be set at this time. See guc.h for the precise
5108          * rules.
5109          */
5110         switch (record->context)
5111         {
5112                 case PGC_INTERNAL:
5113                         if (context != PGC_INTERNAL)
5114                         {
5115                                 ereport(elevel,
5116                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5117                                                  errmsg("parameter \"%s\" cannot be changed",
5118                                                                 name)));
5119                                 return 0;
5120                         }
5121                         break;
5122                 case PGC_POSTMASTER:
5123                         if (context == PGC_SIGHUP)
5124                         {
5125                                 /*
5126                                  * We are re-reading a PGC_POSTMASTER variable from
5127                                  * postgresql.conf.  We can't change the setting, so we should
5128                                  * give a warning if the DBA tries to change it.  However,
5129                                  * because of variant formats, canonicalization by check
5130                                  * hooks, etc, we can't just compare the given string directly
5131                                  * to what's stored.  Set a flag to check below after we have
5132                                  * the final storable value.
5133                                  */
5134                                 prohibitValueChange = true;
5135                         }
5136                         else if (context != PGC_POSTMASTER)
5137                         {
5138                                 ereport(elevel,
5139                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5140                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5141                                                                 name)));
5142                                 return 0;
5143                         }
5144                         break;
5145                 case PGC_SIGHUP:
5146                         if (context != PGC_SIGHUP && context != PGC_POSTMASTER)
5147                         {
5148                                 ereport(elevel,
5149                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5150                                                  errmsg("parameter \"%s\" cannot be changed now",
5151                                                                 name)));
5152                                 return 0;
5153                         }
5154
5155                         /*
5156                          * Hmm, the idea of the SIGHUP context is "ought to be global, but
5157                          * can be changed after postmaster start". But there's nothing
5158                          * that prevents a crafty administrator from sending SIGHUP
5159                          * signals to individual backends only.
5160                          */
5161                         break;
5162                 case PGC_BACKEND:
5163                         if (context == PGC_SIGHUP)
5164                         {
5165                                 /*
5166                                  * If a PGC_BACKEND parameter is changed in the config file,
5167                                  * we want to accept the new value in the postmaster (whence
5168                                  * it will propagate to subsequently-started backends), but
5169                                  * ignore it in existing backends.      This is a tad klugy, but
5170                                  * necessary because we don't re-read the config file during
5171                                  * backend start.
5172                                  */
5173                                 if (IsUnderPostmaster)
5174                                         return -1;
5175                         }
5176                         else if (context != PGC_POSTMASTER && context != PGC_BACKEND &&
5177                                          source != PGC_S_CLIENT)
5178                         {
5179                                 ereport(elevel,
5180                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5181                                                  errmsg("parameter \"%s\" cannot be set after connection start",
5182                                                                 name)));
5183                                 return 0;
5184                         }
5185                         break;
5186                 case PGC_SUSET:
5187                         if (context == PGC_USERSET || context == PGC_BACKEND)
5188                         {
5189                                 ereport(elevel,
5190                                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5191                                                  errmsg("permission denied to set parameter \"%s\"",
5192                                                                 name)));
5193                                 return 0;
5194                         }
5195                         break;
5196                 case PGC_USERSET:
5197                         /* always okay */
5198                         break;
5199         }
5200
5201         /*
5202          * Disallow changing GUC_NOT_WHILE_SEC_REST values if we are inside a
5203          * security restriction context.  We can reject this regardless of the GUC
5204          * context or source, mainly because sources that it might be reasonable
5205          * to override for won't be seen while inside a function.
5206          *
5207          * Note: variables marked GUC_NOT_WHILE_SEC_REST should usually be marked
5208          * GUC_NO_RESET_ALL as well, because ResetAllOptions() doesn't check this.
5209          * An exception might be made if the reset value is assumed to be "safe".
5210          *
5211          * Note: this flag is currently used for "session_authorization" and
5212          * "role".      We need to prohibit changing these inside a local userid
5213          * context because when we exit it, GUC won't be notified, leaving things
5214          * out of sync.  (This could be fixed by forcing a new GUC nesting level,
5215          * but that would change behavior in possibly-undesirable ways.)  Also, we
5216          * prohibit changing these in a security-restricted operation because
5217          * otherwise RESET could be used to regain the session user's privileges.
5218          */
5219         if (record->flags & GUC_NOT_WHILE_SEC_REST)
5220         {
5221                 if (InLocalUserIdChange())
5222                 {
5223                         /*
5224                          * Phrasing of this error message is historical, but it's the most
5225                          * common case.
5226                          */
5227                         ereport(elevel,
5228                                         (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5229                                          errmsg("cannot set parameter \"%s\" within security-definer function",
5230                                                         name)));
5231                         return 0;
5232                 }
5233                 if (InSecurityRestrictedOperation())
5234                 {
5235                         ereport(elevel,
5236                                         (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5237                                          errmsg("cannot set parameter \"%s\" within security-restricted operation",
5238                                                         name)));
5239                         return 0;
5240                 }
5241         }
5242
5243         /*
5244          * Should we set reset/stacked values?  (If so, the behavior is not
5245          * transactional.)      This is done either when we get a default value from
5246          * the database's/user's/client's default settings or when we reset a
5247          * value to its default.
5248          */
5249         makeDefault = changeVal && (source <= PGC_S_OVERRIDE) &&
5250                 ((value != NULL) || source == PGC_S_DEFAULT);
5251
5252         /*
5253          * Ignore attempted set if overridden by previously processed setting.
5254          * However, if changeVal is false then plow ahead anyway since we are
5255          * trying to find out if the value is potentially good, not actually use
5256          * it. Also keep going if makeDefault is true, since we may want to set
5257          * the reset/stacked values even if we can't set the variable itself.
5258          */
5259         if (record->source > source)
5260         {
5261                 if (changeVal && !makeDefault)
5262                 {
5263                         elog(DEBUG3, "\"%s\": setting ignored because previous source is higher priority",
5264                                  name);
5265                         return -1;
5266                 }
5267                 changeVal = false;
5268         }
5269
5270         /*
5271          * Evaluate value and set variable.
5272          */
5273         switch (record->vartype)
5274         {
5275                 case PGC_BOOL:
5276                         {
5277                                 struct config_bool *conf = (struct config_bool *) record;
5278                                 bool            newval;
5279                                 void       *newextra = NULL;
5280
5281                                 if (value)
5282                                 {
5283                                         if (!parse_bool(value, &newval))
5284                                         {
5285                                                 ereport(elevel,
5286                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5287                                                   errmsg("parameter \"%s\" requires a Boolean value",
5288                                                                  name)));
5289                                                 return 0;
5290                                         }
5291                                         if (!call_bool_check_hook(conf, &newval, &newextra,
5292                                                                                           source, elevel))
5293                                                 return 0;
5294                                 }
5295                                 else if (source == PGC_S_DEFAULT)
5296                                 {
5297                                         newval = conf->boot_val;
5298                                         if (!call_bool_check_hook(conf, &newval, &newextra,
5299                                                                                           source, elevel))
5300                                                 return 0;
5301                                 }
5302                                 else
5303                                 {
5304                                         newval = conf->reset_val;
5305                                         newextra = conf->reset_extra;
5306                                         source = conf->gen.reset_source;
5307                                         context = conf->gen.reset_scontext;
5308                                 }
5309
5310                                 if (prohibitValueChange)
5311                                 {
5312                                         if (*conf->variable != newval)
5313                                         {
5314                                                 ereport(elevel,
5315                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5316                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5317                                                                                 name)));
5318                                                 return 0;
5319                                         }
5320                                         return -1;
5321                                 }
5322
5323                                 if (changeVal)
5324                                 {
5325                                         /* Save old value to support transaction abort */
5326                                         if (!makeDefault)
5327                                                 push_old_value(&conf->gen, action);
5328
5329                                         if (conf->assign_hook)
5330                                                 (*conf->assign_hook) (newval, newextra);
5331                                         *conf->variable = newval;
5332                                         set_extra_field(&conf->gen, &conf->gen.extra,
5333                                                                         newextra);
5334                                         conf->gen.source = source;
5335                                         conf->gen.scontext = context;
5336                                 }
5337                                 if (makeDefault)
5338                                 {
5339                                         GucStack   *stack;
5340
5341                                         if (conf->gen.reset_source <= source)
5342                                         {
5343                                                 conf->reset_val = newval;
5344                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5345                                                                                 newextra);
5346                                                 conf->gen.reset_source = source;
5347                                                 conf->gen.reset_scontext = context;
5348                                         }
5349                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5350                                         {
5351                                                 if (stack->source <= source)
5352                                                 {
5353                                                         stack->prior.val.boolval = newval;
5354                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5355                                                                                         newextra);
5356                                                         stack->source = source;
5357                                                         stack->scontext = context;
5358                                                 }
5359                                         }
5360                                 }
5361
5362                                 /* Perhaps we didn't install newextra anywhere */
5363                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5364                                         free(newextra);
5365                                 break;
5366                         }
5367
5368                 case PGC_INT:
5369                         {
5370                                 struct config_int *conf = (struct config_int *) record;
5371                                 int                     newval;
5372                                 void       *newextra = NULL;
5373
5374                                 if (value)
5375                                 {
5376                                         const char *hintmsg;
5377
5378                                         if (!parse_int(value, &newval, conf->gen.flags, &hintmsg))
5379                                         {
5380                                                 ereport(elevel,
5381                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5382                                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
5383                                                                 name, value),
5384                                                                  hintmsg ? errhint("%s", _(hintmsg)) : 0));
5385                                                 return 0;
5386                                         }
5387                                         if (newval < conf->min || newval > conf->max)
5388                                         {
5389                                                 ereport(elevel,
5390                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5391                                                                  errmsg("%d is outside the valid range for parameter \"%s\" (%d .. %d)",
5392                                                                                 newval, name, conf->min, conf->max)));
5393                                                 return 0;
5394                                         }
5395                                         if (!call_int_check_hook(conf, &newval, &newextra,
5396                                                                                          source, elevel))
5397                                                 return 0;
5398                                 }
5399                                 else if (source == PGC_S_DEFAULT)
5400                                 {
5401                                         newval = conf->boot_val;
5402                                         if (!call_int_check_hook(conf, &newval, &newextra,
5403                                                                                          source, elevel))
5404                                                 return 0;
5405                                 }
5406                                 else
5407                                 {
5408                                         newval = conf->reset_val;
5409                                         newextra = conf->reset_extra;
5410                                         source = conf->gen.reset_source;
5411                                         context = conf->gen.reset_scontext;
5412                                 }
5413
5414                                 if (prohibitValueChange)
5415                                 {
5416                                         if (*conf->variable != newval)
5417                                         {
5418                                                 ereport(elevel,
5419                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5420                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5421                                                                                 name)));
5422                                                 return 0;
5423                                         }
5424                                         return -1;
5425                                 }
5426
5427                                 if (changeVal)
5428                                 {
5429                                         /* Save old value to support transaction abort */
5430                                         if (!makeDefault)
5431                                                 push_old_value(&conf->gen, action);
5432
5433                                         if (conf->assign_hook)
5434                                                 (*conf->assign_hook) (newval, newextra);
5435                                         *conf->variable = newval;
5436                                         set_extra_field(&conf->gen, &conf->gen.extra,
5437                                                                         newextra);
5438                                         conf->gen.source = source;
5439                                         conf->gen.scontext = context;
5440                                 }
5441                                 if (makeDefault)
5442                                 {
5443                                         GucStack   *stack;
5444
5445                                         if (conf->gen.reset_source <= source)
5446                                         {
5447                                                 conf->reset_val = newval;
5448                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5449                                                                                 newextra);
5450                                                 conf->gen.reset_source = source;
5451                                                 conf->gen.reset_scontext = context;
5452                                         }
5453                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5454                                         {
5455                                                 if (stack->source <= source)
5456                                                 {
5457                                                         stack->prior.val.intval = newval;
5458                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5459                                                                                         newextra);
5460                                                         stack->source = source;
5461                                                         stack->scontext = context;
5462                                                 }
5463                                         }
5464                                 }
5465
5466                                 /* Perhaps we didn't install newextra anywhere */
5467                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5468                                         free(newextra);
5469                                 break;
5470                         }
5471
5472                 case PGC_REAL:
5473                         {
5474                                 struct config_real *conf = (struct config_real *) record;
5475                                 double          newval;
5476                                 void       *newextra = NULL;
5477
5478                                 if (value)
5479                                 {
5480                                         if (!parse_real(value, &newval))
5481                                         {
5482                                                 ereport(elevel,
5483                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5484                                                   errmsg("parameter \"%s\" requires a numeric value",
5485                                                                  name)));
5486                                                 return 0;
5487                                         }
5488                                         if (newval < conf->min || newval > conf->max)
5489                                         {
5490                                                 ereport(elevel,
5491                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5492                                                                  errmsg("%g is outside the valid range for parameter \"%s\" (%g .. %g)",
5493                                                                                 newval, name, conf->min, conf->max)));
5494                                                 return 0;
5495                                         }
5496                                         if (!call_real_check_hook(conf, &newval, &newextra,
5497                                                                                           source, elevel))
5498                                                 return 0;
5499                                 }
5500                                 else if (source == PGC_S_DEFAULT)
5501                                 {
5502                                         newval = conf->boot_val;
5503                                         if (!call_real_check_hook(conf, &newval, &newextra,
5504                                                                                           source, elevel))
5505                                                 return 0;
5506                                 }
5507                                 else
5508                                 {
5509                                         newval = conf->reset_val;
5510                                         newextra = conf->reset_extra;
5511                                         source = conf->gen.reset_source;
5512                                         context = conf->gen.reset_scontext;
5513                                 }
5514
5515                                 if (prohibitValueChange)
5516                                 {
5517                                         if (*conf->variable != newval)
5518                                         {
5519                                                 ereport(elevel,
5520                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5521                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5522                                                                                 name)));
5523                                                 return 0;
5524                                         }
5525                                         return -1;
5526                                 }
5527
5528                                 if (changeVal)
5529                                 {
5530                                         /* Save old value to support transaction abort */
5531                                         if (!makeDefault)
5532                                                 push_old_value(&conf->gen, action);
5533
5534                                         if (conf->assign_hook)
5535                                                 (*conf->assign_hook) (newval, newextra);
5536                                         *conf->variable = newval;
5537                                         set_extra_field(&conf->gen, &conf->gen.extra,
5538                                                                         newextra);
5539                                         conf->gen.source = source;
5540                                         conf->gen.scontext = context;
5541                                 }
5542                                 if (makeDefault)
5543                                 {
5544                                         GucStack   *stack;
5545
5546                                         if (conf->gen.reset_source <= source)
5547                                         {
5548                                                 conf->reset_val = newval;
5549                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5550                                                                                 newextra);
5551                                                 conf->gen.reset_source = source;
5552                                                 conf->gen.reset_scontext = context;
5553                                         }
5554                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5555                                         {
5556                                                 if (stack->source <= source)
5557                                                 {
5558                                                         stack->prior.val.realval = newval;
5559                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5560                                                                                         newextra);
5561                                                         stack->source = source;
5562                                                         stack->scontext = context;
5563                                                 }
5564                                         }
5565                                 }
5566
5567                                 /* Perhaps we didn't install newextra anywhere */
5568                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5569                                         free(newextra);
5570                                 break;
5571                         }
5572
5573                 case PGC_STRING:
5574                         {
5575                                 struct config_string *conf = (struct config_string *) record;
5576                                 char       *newval;
5577                                 void       *newextra = NULL;
5578
5579                                 if (value)
5580                                 {
5581                                         /*
5582                                          * The value passed by the caller could be transient, so
5583                                          * we always strdup it.
5584                                          */
5585                                         newval = guc_strdup(elevel, value);
5586                                         if (newval == NULL)
5587                                                 return 0;
5588
5589                                         /*
5590                                          * The only built-in "parsing" check we have is to apply
5591                                          * truncation if GUC_IS_NAME.
5592                                          */
5593                                         if (conf->gen.flags & GUC_IS_NAME)
5594                                                 truncate_identifier(newval, strlen(newval), true);
5595
5596                                         if (!call_string_check_hook(conf, &newval, &newextra,
5597                                                                                                 source, elevel))
5598                                         {
5599                                                 free(newval);
5600                                                 return 0;
5601                                         }
5602                                 }
5603                                 else if (source == PGC_S_DEFAULT)
5604                                 {
5605                                         /* non-NULL boot_val must always get strdup'd */
5606                                         if (conf->boot_val != NULL)
5607                                         {
5608                                                 newval = guc_strdup(elevel, conf->boot_val);
5609                                                 if (newval == NULL)
5610                                                         return 0;
5611                                         }
5612                                         else
5613                                                 newval = NULL;
5614
5615                                         if (!call_string_check_hook(conf, &newval, &newextra,
5616                                                                                                 source, elevel))
5617                                         {
5618                                                 free(newval);
5619                                                 return 0;
5620                                         }
5621                                 }
5622                                 else
5623                                 {
5624                                         /*
5625                                          * strdup not needed, since reset_val is already under
5626                                          * guc.c's control
5627                                          */
5628                                         newval = conf->reset_val;
5629                                         newextra = conf->reset_extra;
5630                                         source = conf->gen.reset_source;
5631                                         context = conf->gen.reset_scontext;
5632                                 }
5633
5634                                 if (prohibitValueChange)
5635                                 {
5636                                         /* newval shouldn't be NULL, so we're a bit sloppy here */
5637                                         if (*conf->variable == NULL || newval == NULL ||
5638                                                 strcmp(*conf->variable, newval) != 0)
5639                                         {
5640                                                 ereport(elevel,
5641                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5642                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5643                                                                                 name)));
5644                                                 return 0;
5645                                         }
5646                                         return -1;
5647                                 }
5648
5649                                 if (changeVal)
5650                                 {
5651                                         /* Save old value to support transaction abort */
5652                                         if (!makeDefault)
5653                                                 push_old_value(&conf->gen, action);
5654
5655                                         if (conf->assign_hook)
5656                                                 (*conf->assign_hook) (newval, newextra);
5657                                         set_string_field(conf, conf->variable, newval);
5658                                         set_extra_field(&conf->gen, &conf->gen.extra,
5659                                                                         newextra);
5660                                         conf->gen.source = source;
5661                                         conf->gen.scontext = context;
5662                                 }
5663
5664                                 if (makeDefault)
5665                                 {
5666                                         GucStack   *stack;
5667
5668                                         if (conf->gen.reset_source <= source)
5669                                         {
5670                                                 set_string_field(conf, &conf->reset_val, newval);
5671                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5672                                                                                 newextra);
5673                                                 conf->gen.reset_source = source;
5674                                                 conf->gen.reset_scontext = context;
5675                                         }
5676                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5677                                         {
5678                                                 if (stack->source <= source)
5679                                                 {
5680                                                         set_string_field(conf, &stack->prior.val.stringval,
5681                                                                                          newval);
5682                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5683                                                                                         newextra);
5684                                                         stack->source = source;
5685                                                         stack->scontext = context;
5686                                                 }
5687                                         }
5688                                 }
5689
5690                                 /* Perhaps we didn't install newval anywhere */
5691                                 if (newval && !string_field_used(conf, newval))
5692                                         free(newval);
5693                                 /* Perhaps we didn't install newextra anywhere */
5694                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5695                                         free(newextra);
5696                                 break;
5697                         }
5698
5699                 case PGC_ENUM:
5700                         {
5701                                 struct config_enum *conf = (struct config_enum *) record;
5702                                 int                     newval;
5703                                 void       *newextra = NULL;
5704
5705                                 if (value)
5706                                 {
5707                                         if (!config_enum_lookup_by_name(conf, value, &newval))
5708                                         {
5709                                                 char       *hintmsg;
5710
5711                                                 hintmsg = config_enum_get_options(conf,
5712                                                                                                                 "Available values: ",
5713                                                                                                                   ".", ", ");
5714
5715                                                 ereport(elevel,
5716                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5717                                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
5718                                                                 name, value),
5719                                                                  hintmsg ? errhint("%s", _(hintmsg)) : 0));
5720
5721                                                 if (hintmsg)
5722                                                         pfree(hintmsg);
5723                                                 return 0;
5724                                         }
5725                                         if (!call_enum_check_hook(conf, &newval, &newextra,
5726                                                                                           source, elevel))
5727                                                 return 0;
5728                                 }
5729                                 else if (source == PGC_S_DEFAULT)
5730                                 {
5731                                         newval = conf->boot_val;
5732                                         if (!call_enum_check_hook(conf, &newval, &newextra,
5733                                                                                           source, elevel))
5734                                                 return 0;
5735                                 }
5736                                 else
5737                                 {
5738                                         newval = conf->reset_val;
5739                                         newextra = conf->reset_extra;
5740                                         source = conf->gen.reset_source;
5741                                         context = conf->gen.reset_scontext;
5742                                 }
5743
5744                                 if (prohibitValueChange)
5745                                 {
5746                                         if (*conf->variable != newval)
5747                                         {
5748                                                 ereport(elevel,
5749                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5750                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5751                                                                                 name)));
5752                                                 return 0;
5753                                         }
5754                                         return -1;
5755                                 }
5756
5757                                 if (changeVal)
5758                                 {
5759                                         /* Save old value to support transaction abort */
5760                                         if (!makeDefault)
5761                                                 push_old_value(&conf->gen, action);
5762
5763                                         if (conf->assign_hook)
5764                                                 (*conf->assign_hook) (newval, newextra);
5765                                         *conf->variable = newval;
5766                                         set_extra_field(&conf->gen, &conf->gen.extra,
5767                                                                         newextra);
5768                                         conf->gen.source = source;
5769                                         conf->gen.scontext = context;
5770                                 }
5771                                 if (makeDefault)
5772                                 {
5773                                         GucStack   *stack;
5774
5775                                         if (conf->gen.reset_source <= source)
5776                                         {
5777                                                 conf->reset_val = newval;
5778                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5779                                                                                 newextra);
5780                                                 conf->gen.reset_source = source;
5781                                                 conf->gen.reset_scontext = context;
5782                                         }
5783                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5784                                         {
5785                                                 if (stack->source <= source)
5786                                                 {
5787                                                         stack->prior.val.enumval = newval;
5788                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5789                                                                                         newextra);
5790                                                         stack->source = source;
5791                                                         stack->scontext = context;
5792                                                 }
5793                                         }
5794                                 }
5795
5796                                 /* Perhaps we didn't install newextra anywhere */
5797                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5798                                         free(newextra);
5799                                 break;
5800                         }
5801         }
5802
5803         if (changeVal && (record->flags & GUC_REPORT))
5804                 ReportGUCOption(record);
5805
5806         return changeVal ? 1 : -1;
5807 }
5808
5809
5810 /*
5811  * Set the fields for source file and line number the setting came from.
5812  */
5813 static void
5814 set_config_sourcefile(const char *name, char *sourcefile, int sourceline)
5815 {
5816         struct config_generic *record;
5817         int                     elevel;
5818
5819         /*
5820          * To avoid cluttering the log, only the postmaster bleats loudly about
5821          * problems with the config file.
5822          */
5823         elevel = IsUnderPostmaster ? DEBUG3 : LOG;
5824
5825         record = find_option(name, true, elevel);
5826         /* should not happen */
5827         if (record == NULL)
5828                 elog(ERROR, "unrecognized configuration parameter \"%s\"", name);
5829
5830         sourcefile = guc_strdup(elevel, sourcefile);
5831         if (record->sourcefile)
5832                 free(record->sourcefile);
5833         record->sourcefile = sourcefile;
5834         record->sourceline = sourceline;
5835 }
5836
5837 /*
5838  * Set a config option to the given value.
5839  *
5840  * See also set_config_option; this is just the wrapper to be called from
5841  * outside GUC.  (This function should be used when possible, because its API
5842  * is more stable than set_config_option's.)
5843  *
5844  * Note: there is no support here for setting source file/line, as it
5845  * is currently not needed.
5846  */
5847 void
5848 SetConfigOption(const char *name, const char *value,
5849                                 GucContext context, GucSource source)
5850 {
5851         (void) set_config_option(name, value, context, source,
5852                                                          GUC_ACTION_SET, true, 0);
5853 }
5854
5855
5856
5857 /*
5858  * Fetch the current value of the option `name', as a string.
5859  *
5860  * If the option doesn't exist, return NULL if missing_ok is true (NOTE that
5861  * this cannot be distinguished from a string variable with a NULL value!),
5862  * otherwise throw an ereport and don't return.
5863  *
5864  * If restrict_superuser is true, we also enforce that only superusers can
5865  * see GUC_SUPERUSER_ONLY variables.  This should only be passed as true
5866  * in user-driven calls.
5867  *
5868  * The string is *not* allocated for modification and is really only
5869  * valid until the next call to configuration related functions.
5870  */
5871 const char *
5872 GetConfigOption(const char *name, bool missing_ok, bool restrict_superuser)
5873 {
5874         struct config_generic *record;
5875         static char buffer[256];
5876
5877         record = find_option(name, false, ERROR);
5878         if (record == NULL)
5879         {
5880                 if (missing_ok)
5881                         return NULL;
5882                 ereport(ERROR,
5883                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
5884                                  errmsg("unrecognized configuration parameter \"%s\"",
5885                                                 name)));
5886         }
5887         if (restrict_superuser &&
5888                 (record->flags & GUC_SUPERUSER_ONLY) &&
5889                 !superuser())
5890                 ereport(ERROR,
5891                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5892                                  errmsg("must be superuser to examine \"%s\"", name)));
5893
5894         switch (record->vartype)
5895         {
5896                 case PGC_BOOL:
5897                         return *((struct config_bool *) record)->variable ? "on" : "off";
5898
5899                 case PGC_INT:
5900                         snprintf(buffer, sizeof(buffer), "%d",
5901                                          *((struct config_int *) record)->variable);
5902                         return buffer;
5903
5904                 case PGC_REAL:
5905                         snprintf(buffer, sizeof(buffer), "%g",
5906                                          *((struct config_real *) record)->variable);
5907                         return buffer;
5908
5909                 case PGC_STRING:
5910                         return *((struct config_string *) record)->variable;
5911
5912                 case PGC_ENUM:
5913                         return config_enum_lookup_by_value((struct config_enum *) record,
5914                                                                  *((struct config_enum *) record)->variable);
5915         }
5916         return NULL;
5917 }
5918
5919 /*
5920  * Get the RESET value associated with the given option.
5921  *
5922  * Note: this is not re-entrant, due to use of static result buffer;
5923  * not to mention that a string variable could have its reset_val changed.
5924  * Beware of assuming the result value is good for very long.
5925  */
5926 const char *
5927 GetConfigOptionResetString(const char *name)
5928 {
5929         struct config_generic *record;
5930         static char buffer[256];
5931
5932         record = find_option(name, false, ERROR);
5933         if (record == NULL)
5934                 ereport(ERROR,
5935                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
5936                            errmsg("unrecognized configuration parameter \"%s\"", name)));
5937         if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
5938                 ereport(ERROR,
5939                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5940                                  errmsg("must be superuser to examine \"%s\"", name)));
5941
5942         switch (record->vartype)
5943         {
5944                 case PGC_BOOL:
5945                         return ((struct config_bool *) record)->reset_val ? "on" : "off";
5946
5947                 case PGC_INT:
5948                         snprintf(buffer, sizeof(buffer), "%d",
5949                                          ((struct config_int *) record)->reset_val);
5950                         return buffer;
5951
5952                 case PGC_REAL:
5953                         snprintf(buffer, sizeof(buffer), "%g",
5954                                          ((struct config_real *) record)->reset_val);
5955                         return buffer;
5956
5957                 case PGC_STRING:
5958                         return ((struct config_string *) record)->reset_val;
5959
5960                 case PGC_ENUM:
5961                         return config_enum_lookup_by_value((struct config_enum *) record,
5962                                                                  ((struct config_enum *) record)->reset_val);
5963         }
5964         return NULL;
5965 }
5966
5967
5968 /*
5969  * flatten_set_variable_args
5970  *              Given a parsenode List as emitted by the grammar for SET,
5971  *              convert to the flat string representation used by GUC.
5972  *
5973  * We need to be told the name of the variable the args are for, because
5974  * the flattening rules vary (ugh).
5975  *
5976  * The result is NULL if args is NIL (ie, SET ... TO DEFAULT), otherwise
5977  * a palloc'd string.
5978  */
5979 static char *
5980 flatten_set_variable_args(const char *name, List *args)
5981 {
5982         struct config_generic *record;
5983         int                     flags;
5984         StringInfoData buf;
5985         ListCell   *l;
5986
5987         /* Fast path if just DEFAULT */
5988         if (args == NIL)
5989                 return NULL;
5990
5991         /*
5992          * Get flags for the variable; if it's not known, use default flags.
5993          * (Caller might throw error later, but not our business to do so here.)
5994          */
5995         record = find_option(name, false, WARNING);
5996         if (record)
5997                 flags = record->flags;
5998         else
5999                 flags = 0;
6000
6001         /* Complain if list input and non-list variable */
6002         if ((flags & GUC_LIST_INPUT) == 0 &&
6003                 list_length(args) != 1)
6004                 ereport(ERROR,
6005                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6006                                  errmsg("SET %s takes only one argument", name)));
6007
6008         initStringInfo(&buf);
6009
6010         /*
6011          * Each list member may be a plain A_Const node, or an A_Const within a
6012          * TypeCast; the latter case is supported only for ConstInterval arguments
6013          * (for SET TIME ZONE).
6014          */
6015         foreach(l, args)
6016         {
6017                 Node       *arg = (Node *) lfirst(l);
6018                 char       *val;
6019                 TypeName   *typeName = NULL;
6020                 A_Const    *con;
6021
6022                 if (l != list_head(args))
6023                         appendStringInfo(&buf, ", ");
6024
6025                 if (IsA(arg, TypeCast))
6026                 {
6027                         TypeCast   *tc = (TypeCast *) arg;
6028
6029                         arg = tc->arg;
6030                         typeName = tc->typeName;
6031                 }
6032
6033                 if (!IsA(arg, A_Const))
6034                         elog(ERROR, "unrecognized node type: %d", (int) nodeTag(arg));
6035                 con = (A_Const *) arg;
6036
6037                 switch (nodeTag(&con->val))
6038                 {
6039                         case T_Integer:
6040                                 appendStringInfo(&buf, "%ld", intVal(&con->val));
6041                                 break;
6042                         case T_Float:
6043                                 /* represented as a string, so just copy it */
6044                                 appendStringInfoString(&buf, strVal(&con->val));
6045                                 break;
6046                         case T_String:
6047                                 val = strVal(&con->val);
6048                                 if (typeName != NULL)
6049                                 {
6050                                         /*
6051                                          * Must be a ConstInterval argument for TIME ZONE. Coerce
6052                                          * to interval and back to normalize the value and account
6053                                          * for any typmod.
6054                                          */
6055                                         Oid                     typoid;
6056                                         int32           typmod;
6057                                         Datum           interval;
6058                                         char       *intervalout;
6059
6060                                         typenameTypeIdAndMod(NULL, typeName, &typoid, &typmod);
6061                                         Assert(typoid == INTERVALOID);
6062
6063                                         interval =
6064                                                 DirectFunctionCall3(interval_in,
6065                                                                                         CStringGetDatum(val),
6066                                                                                         ObjectIdGetDatum(InvalidOid),
6067                                                                                         Int32GetDatum(typmod));
6068
6069                                         intervalout =
6070                                                 DatumGetCString(DirectFunctionCall1(interval_out,
6071                                                                                                                         interval));
6072                                         appendStringInfo(&buf, "INTERVAL '%s'", intervalout);
6073                                 }
6074                                 else
6075                                 {
6076                                         /*
6077                                          * Plain string literal or identifier.  For quote mode,
6078                                          * quote it if it's not a vanilla identifier.
6079                                          */
6080                                         if (flags & GUC_LIST_QUOTE)
6081                                                 appendStringInfoString(&buf, quote_identifier(val));
6082                                         else
6083                                                 appendStringInfoString(&buf, val);
6084                                 }
6085                                 break;
6086                         default:
6087                                 elog(ERROR, "unrecognized node type: %d",
6088                                          (int) nodeTag(&con->val));
6089                                 break;
6090                 }
6091         }
6092
6093         return buf.data;
6094 }
6095
6096
6097 /*
6098  * SET command
6099  */
6100 void
6101 ExecSetVariableStmt(VariableSetStmt *stmt)
6102 {
6103         GucAction       action = stmt->is_local ? GUC_ACTION_LOCAL : GUC_ACTION_SET;
6104
6105         switch (stmt->kind)
6106         {
6107                 case VAR_SET_VALUE:
6108                 case VAR_SET_CURRENT:
6109                         (void) set_config_option(stmt->name,
6110                                                                          ExtractSetVariableArgs(stmt),
6111                                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6112                                                                          PGC_S_SESSION,
6113                                                                          action,
6114                                                                          true,
6115                                                                          0);
6116                         break;
6117                 case VAR_SET_MULTI:
6118
6119                         /*
6120                          * Special-case SQL syntaxes.  The TRANSACTION and SESSION
6121                          * CHARACTERISTICS cases effectively set more than one variable
6122                          * per statement.  TRANSACTION SNAPSHOT only takes one argument,
6123                          * but we put it here anyway since it's a special case and not
6124                          * related to any GUC variable.
6125                          */
6126                         if (strcmp(stmt->name, "TRANSACTION") == 0)
6127                         {
6128                                 ListCell   *head;
6129
6130                                 foreach(head, stmt->args)
6131                                 {
6132                                         DefElem    *item = (DefElem *) lfirst(head);
6133
6134                                         if (strcmp(item->defname, "transaction_isolation") == 0)
6135                                                 SetPGVariable("transaction_isolation",
6136                                                                           list_make1(item->arg), stmt->is_local);
6137                                         else if (strcmp(item->defname, "transaction_read_only") == 0)
6138                                                 SetPGVariable("transaction_read_only",
6139                                                                           list_make1(item->arg), stmt->is_local);
6140                                         else if (strcmp(item->defname, "transaction_deferrable") == 0)
6141                                                 SetPGVariable("transaction_deferrable",
6142                                                                           list_make1(item->arg), stmt->is_local);
6143                                         else
6144                                                 elog(ERROR, "unexpected SET TRANSACTION element: %s",
6145                                                          item->defname);
6146                                 }
6147                         }
6148                         else if (strcmp(stmt->name, "SESSION CHARACTERISTICS") == 0)
6149                         {
6150                                 ListCell   *head;
6151
6152                                 foreach(head, stmt->args)
6153                                 {
6154                                         DefElem    *item = (DefElem *) lfirst(head);
6155
6156                                         if (strcmp(item->defname, "transaction_isolation") == 0)
6157                                                 SetPGVariable("default_transaction_isolation",
6158                                                                           list_make1(item->arg), stmt->is_local);
6159                                         else if (strcmp(item->defname, "transaction_read_only") == 0)
6160                                                 SetPGVariable("default_transaction_read_only",
6161                                                                           list_make1(item->arg), stmt->is_local);
6162                                         else if (strcmp(item->defname, "transaction_deferrable") == 0)
6163                                                 SetPGVariable("default_transaction_deferrable",
6164                                                                           list_make1(item->arg), stmt->is_local);
6165                                         else
6166                                                 elog(ERROR, "unexpected SET SESSION element: %s",
6167                                                          item->defname);
6168                                 }
6169                         }
6170                         else if (strcmp(stmt->name, "TRANSACTION SNAPSHOT") == 0)
6171                         {
6172                                 A_Const    *con = (A_Const *) linitial(stmt->args);
6173
6174                                 if (stmt->is_local)
6175                                         ereport(ERROR,
6176                                                         (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6177                                                          errmsg("SET LOCAL TRANSACTION SNAPSHOT is not implemented")));
6178                                 Assert(IsA(con, A_Const));
6179                                 Assert(nodeTag(&con->val) == T_String);
6180                                 ImportSnapshot(strVal(&con->val));
6181                         }
6182                         else
6183                                 elog(ERROR, "unexpected SET MULTI element: %s",
6184                                          stmt->name);
6185                         break;
6186                 case VAR_SET_DEFAULT:
6187                 case VAR_RESET:
6188                         (void) set_config_option(stmt->name,
6189                                                                          NULL,
6190                                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6191                                                                          PGC_S_SESSION,
6192                                                                          action,
6193                                                                          true,
6194                                                                          0);
6195                         break;
6196                 case VAR_RESET_ALL:
6197                         ResetAllOptions();
6198                         break;
6199         }
6200 }
6201
6202 /*
6203  * Get the value to assign for a VariableSetStmt, or NULL if it's RESET.
6204  * The result is palloc'd.
6205  *
6206  * This is exported for use by actions such as ALTER ROLE SET.
6207  */
6208 char *
6209 ExtractSetVariableArgs(VariableSetStmt *stmt)
6210 {
6211         switch (stmt->kind)
6212         {
6213                 case VAR_SET_VALUE:
6214                         return flatten_set_variable_args(stmt->name, stmt->args);
6215                 case VAR_SET_CURRENT:
6216                         return GetConfigOptionByName(stmt->name, NULL);
6217                 default:
6218                         return NULL;
6219         }
6220 }
6221
6222 /*
6223  * SetPGVariable - SET command exported as an easily-C-callable function.
6224  *
6225  * This provides access to SET TO value, as well as SET TO DEFAULT (expressed
6226  * by passing args == NIL), but not SET FROM CURRENT functionality.
6227  */
6228 void
6229 SetPGVariable(const char *name, List *args, bool is_local)
6230 {
6231         char       *argstring = flatten_set_variable_args(name, args);
6232
6233         /* Note SET DEFAULT (argstring == NULL) is equivalent to RESET */
6234         (void) set_config_option(name,
6235                                                          argstring,
6236                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6237                                                          PGC_S_SESSION,
6238                                                          is_local ? GUC_ACTION_LOCAL : GUC_ACTION_SET,
6239                                                          true,
6240                                                          0);
6241 }
6242
6243 /*
6244  * SET command wrapped as a SQL callable function.
6245  */
6246 Datum
6247 set_config_by_name(PG_FUNCTION_ARGS)
6248 {
6249         char       *name;
6250         char       *value;
6251         char       *new_value;
6252         bool            is_local;
6253
6254         if (PG_ARGISNULL(0))
6255                 ereport(ERROR,
6256                                 (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
6257                                  errmsg("SET requires parameter name")));
6258
6259         /* Get the GUC variable name */
6260         name = TextDatumGetCString(PG_GETARG_DATUM(0));
6261
6262         /* Get the desired value or set to NULL for a reset request */
6263         if (PG_ARGISNULL(1))
6264                 value = NULL;
6265         else
6266                 value = TextDatumGetCString(PG_GETARG_DATUM(1));
6267
6268         /*
6269          * Get the desired state of is_local. Default to false if provided value
6270          * is NULL
6271          */
6272         if (PG_ARGISNULL(2))
6273                 is_local = false;
6274         else
6275                 is_local = PG_GETARG_BOOL(2);
6276
6277         /* Note SET DEFAULT (argstring == NULL) is equivalent to RESET */
6278         (void) set_config_option(name,
6279                                                          value,
6280                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6281                                                          PGC_S_SESSION,
6282                                                          is_local ? GUC_ACTION_LOCAL : GUC_ACTION_SET,
6283                                                          true,
6284                                                          0);
6285
6286         /* get the new current value */
6287         new_value = GetConfigOptionByName(name, NULL);
6288
6289         /* Convert return string to text */
6290         PG_RETURN_TEXT_P(cstring_to_text(new_value));
6291 }
6292
6293
6294 /*
6295  * Common code for DefineCustomXXXVariable subroutines: allocate the
6296  * new variable's config struct and fill in generic fields.
6297  */
6298 static struct config_generic *
6299 init_custom_variable(const char *name,
6300                                          const char *short_desc,
6301                                          const char *long_desc,
6302                                          GucContext context,
6303                                          int flags,
6304                                          enum config_type type,
6305                                          size_t sz)
6306 {
6307         struct config_generic *gen;
6308
6309         /*
6310          * Only allow custom PGC_POSTMASTER variables to be created during shared
6311          * library preload; any later than that, we can't ensure that the value
6312          * doesn't change after startup.  This is a fatal elog if it happens; just
6313          * erroring out isn't safe because we don't know what the calling loadable
6314          * module might already have hooked into.
6315          */
6316         if (context == PGC_POSTMASTER &&
6317                 !process_shared_preload_libraries_in_progress)
6318                 elog(FATAL, "cannot create PGC_POSTMASTER variables after startup");
6319
6320         gen = (struct config_generic *) guc_malloc(ERROR, sz);
6321         memset(gen, 0, sz);
6322
6323         gen->name = guc_strdup(ERROR, name);
6324         gen->context = context;
6325         gen->group = CUSTOM_OPTIONS;
6326         gen->short_desc = short_desc;
6327         gen->long_desc = long_desc;
6328         gen->flags = flags;
6329         gen->vartype = type;
6330
6331         return gen;
6332 }
6333
6334 /*
6335  * Common code for DefineCustomXXXVariable subroutines: insert the new
6336  * variable into the GUC variable array, replacing any placeholder.
6337  */
6338 static void
6339 define_custom_variable(struct config_generic * variable)
6340 {
6341         const char *name = variable->name;
6342         const char **nameAddr = &name;
6343         struct config_string *pHolder;
6344         struct config_generic **res;
6345
6346         /*
6347          * See if there's a placeholder by the same name.
6348          */
6349         res = (struct config_generic **) bsearch((void *) &nameAddr,
6350                                                                                          (void *) guc_variables,
6351                                                                                          num_guc_variables,
6352                                                                                          sizeof(struct config_generic *),
6353                                                                                          guc_var_compare);
6354         if (res == NULL)
6355         {
6356                 /*
6357                  * No placeholder to replace, so we can just add it ... but first,
6358                  * make sure it's initialized to its default value.
6359                  */
6360                 InitializeOneGUCOption(variable);
6361                 add_guc_variable(variable, ERROR);
6362                 return;
6363         }
6364
6365         /*
6366          * This better be a placeholder
6367          */
6368         if (((*res)->flags & GUC_CUSTOM_PLACEHOLDER) == 0)
6369                 ereport(ERROR,
6370                                 (errcode(ERRCODE_INTERNAL_ERROR),
6371                                  errmsg("attempt to redefine parameter \"%s\"", name)));
6372
6373         Assert((*res)->vartype == PGC_STRING);
6374         pHolder = (struct config_string *) (*res);
6375
6376         /*
6377          * First, set the variable to its default value.  We must do this even
6378          * though we intend to immediately apply a new value, since it's possible
6379          * that the new value is invalid.
6380          */
6381         InitializeOneGUCOption(variable);
6382
6383         /*
6384          * Replace the placeholder. We aren't changing the name, so no re-sorting
6385          * is necessary
6386          */
6387         *res = variable;
6388
6389         /*
6390          * Assign the string value(s) stored in the placeholder to the real
6391          * variable.  Essentially, we need to duplicate all the active and stacked
6392          * values, but with appropriate validation and datatype adjustment.
6393          *
6394          * If an assignment fails, we report a WARNING and keep going.  We don't
6395          * want to throw ERROR for bad values, because it'd bollix the add-on
6396          * module that's presumably halfway through getting loaded.  In such cases
6397          * the default or previous state will become active instead.
6398          */
6399
6400         /* First, apply the reset value if any */
6401         if (pHolder->reset_val)
6402                 (void) set_config_option(name, pHolder->reset_val,
6403                                                                  pHolder->gen.reset_scontext,
6404                                                                  pHolder->gen.reset_source,
6405                                                                  GUC_ACTION_SET, true, WARNING);
6406         /* That should not have resulted in stacking anything */
6407         Assert(variable->stack == NULL);
6408
6409         /* Now, apply current and stacked values, in the order they were stacked */
6410         reapply_stacked_values(variable, pHolder, pHolder->gen.stack,
6411                                                    *(pHolder->variable),
6412                                                    pHolder->gen.scontext, pHolder->gen.source);
6413
6414         /* Also copy over any saved source-location information */
6415         if (pHolder->gen.sourcefile)
6416                 set_config_sourcefile(name, pHolder->gen.sourcefile,
6417                                                           pHolder->gen.sourceline);
6418
6419         /*
6420          * Free up as much as we conveniently can of the placeholder structure.
6421          * (This neglects any stack items, so it's possible for some memory to be
6422          * leaked.  Since this can only happen once per session per variable, it
6423          * doesn't seem worth spending much code on.)
6424          */
6425         set_string_field(pHolder, pHolder->variable, NULL);
6426         set_string_field(pHolder, &pHolder->reset_val, NULL);
6427
6428         free(pHolder);
6429 }
6430
6431 /*
6432  * Recursive subroutine for define_custom_variable: reapply non-reset values
6433  *
6434  * We recurse so that the values are applied in the same order as originally.
6435  * At each recursion level, apply the upper-level value (passed in) in the
6436  * fashion implied by the stack entry.
6437  */
6438 static void
6439 reapply_stacked_values(struct config_generic * variable,
6440                                            struct config_string *pHolder,
6441                                            GucStack *stack,
6442                                            const char *curvalue,
6443                                            GucContext curscontext, GucSource cursource)
6444 {
6445         const char *name = variable->name;
6446         GucStack   *oldvarstack = variable->stack;
6447
6448         if (stack != NULL)
6449         {
6450                 /* First, recurse, so that stack items are processed bottom to top */
6451                 reapply_stacked_values(variable, pHolder, stack->prev,
6452                                                            stack->prior.val.stringval,
6453                                                            stack->scontext, stack->source);
6454
6455                 /* See how to apply the passed-in value */
6456                 switch (stack->state)
6457                 {
6458                         case GUC_SAVE:
6459                                 (void) set_config_option(name, curvalue,
6460                                                                                  curscontext, cursource,
6461                                                                                  GUC_ACTION_SAVE, true, WARNING);
6462                                 break;
6463
6464                         case GUC_SET:
6465                                 (void) set_config_option(name, curvalue,
6466                                                                                  curscontext, cursource,
6467                                                                                  GUC_ACTION_SET, true, WARNING);
6468                                 break;
6469
6470                         case GUC_LOCAL:
6471                                 (void) set_config_option(name, curvalue,
6472                                                                                  curscontext, cursource,
6473                                                                                  GUC_ACTION_LOCAL, true, WARNING);
6474                                 break;
6475
6476                         case GUC_SET_LOCAL:
6477                                 /* first, apply the masked value as SET */
6478                                 (void) set_config_option(name, stack->masked.val.stringval,
6479                                                                                  stack->masked_scontext, PGC_S_SESSION,
6480                                                                                  GUC_ACTION_SET, true, WARNING);
6481                                 /* then apply the current value as LOCAL */
6482                                 (void) set_config_option(name, curvalue,
6483                                                                                  curscontext, cursource,
6484                                                                                  GUC_ACTION_LOCAL, true, WARNING);
6485                                 break;
6486                 }
6487
6488                 /* If we successfully made a stack entry, adjust its nest level */
6489                 if (variable->stack != oldvarstack)
6490                         variable->stack->nest_level = stack->nest_level;
6491         }
6492         else
6493         {
6494                 /*
6495                  * We are at the end of the stack.  If the active/previous value is
6496                  * different from the reset value, it must represent a previously
6497                  * committed session value.  Apply it, and then drop the stack entry
6498                  * that set_config_option will have created under the impression that
6499                  * this is to be just a transactional assignment.  (We leak the stack
6500                  * entry.)
6501                  */
6502                 if (curvalue != pHolder->reset_val ||
6503                         curscontext != pHolder->gen.reset_scontext ||
6504                         cursource != pHolder->gen.reset_source)
6505                 {
6506                         (void) set_config_option(name, curvalue,
6507                                                                          curscontext, cursource,
6508                                                                          GUC_ACTION_SET, true, WARNING);
6509                         variable->stack = NULL;
6510                 }
6511         }
6512 }
6513
6514 void
6515 DefineCustomBoolVariable(const char *name,
6516                                                  const char *short_desc,
6517                                                  const char *long_desc,
6518                                                  bool *valueAddr,
6519                                                  bool bootValue,
6520                                                  GucContext context,
6521                                                  int flags,
6522                                                  GucBoolCheckHook check_hook,
6523                                                  GucBoolAssignHook assign_hook,
6524                                                  GucShowHook show_hook)
6525 {
6526         struct config_bool *var;
6527
6528         var = (struct config_bool *)
6529                 init_custom_variable(name, short_desc, long_desc, context, flags,
6530                                                          PGC_BOOL, sizeof(struct config_bool));
6531         var->variable = valueAddr;
6532         var->boot_val = bootValue;
6533         var->reset_val = bootValue;
6534         var->check_hook = check_hook;
6535         var->assign_hook = assign_hook;
6536         var->show_hook = show_hook;
6537         define_custom_variable(&var->gen);
6538 }
6539
6540 void
6541 DefineCustomIntVariable(const char *name,
6542                                                 const char *short_desc,
6543                                                 const char *long_desc,
6544                                                 int *valueAddr,
6545                                                 int bootValue,
6546                                                 int minValue,
6547                                                 int maxValue,
6548                                                 GucContext context,
6549                                                 int flags,
6550                                                 GucIntCheckHook check_hook,
6551                                                 GucIntAssignHook assign_hook,
6552                                                 GucShowHook show_hook)
6553 {
6554         struct config_int *var;
6555
6556         var = (struct config_int *)
6557                 init_custom_variable(name, short_desc, long_desc, context, flags,
6558                                                          PGC_INT, sizeof(struct config_int));
6559         var->variable = valueAddr;
6560         var->boot_val = bootValue;
6561         var->reset_val = bootValue;
6562         var->min = minValue;
6563         var->max = maxValue;
6564         var->check_hook = check_hook;
6565         var->assign_hook = assign_hook;
6566         var->show_hook = show_hook;
6567         define_custom_variable(&var->gen);
6568 }
6569
6570 void
6571 DefineCustomRealVariable(const char *name,
6572                                                  const char *short_desc,
6573                                                  const char *long_desc,
6574                                                  double *valueAddr,
6575                                                  double bootValue,
6576                                                  double minValue,
6577                                                  double maxValue,
6578                                                  GucContext context,
6579                                                  int flags,
6580                                                  GucRealCheckHook check_hook,
6581                                                  GucRealAssignHook assign_hook,
6582                                                  GucShowHook show_hook)
6583 {
6584         struct config_real *var;
6585
6586         var = (struct config_real *)
6587                 init_custom_variable(name, short_desc, long_desc, context, flags,
6588                                                          PGC_REAL, sizeof(struct config_real));
6589         var->variable = valueAddr;
6590         var->boot_val = bootValue;
6591         var->reset_val = bootValue;
6592         var->min = minValue;
6593         var->max = maxValue;
6594         var->check_hook = check_hook;
6595         var->assign_hook = assign_hook;
6596         var->show_hook = show_hook;
6597         define_custom_variable(&var->gen);
6598 }
6599
6600 void
6601 DefineCustomStringVariable(const char *name,
6602                                                    const char *short_desc,
6603                                                    const char *long_desc,
6604                                                    char **valueAddr,
6605                                                    const char *bootValue,
6606                                                    GucContext context,
6607                                                    int flags,
6608                                                    GucStringCheckHook check_hook,
6609                                                    GucStringAssignHook assign_hook,
6610                                                    GucShowHook show_hook)
6611 {
6612         struct config_string *var;
6613
6614         var = (struct config_string *)
6615                 init_custom_variable(name, short_desc, long_desc, context, flags,
6616                                                          PGC_STRING, sizeof(struct config_string));
6617         var->variable = valueAddr;
6618         var->boot_val = bootValue;
6619         var->check_hook = check_hook;
6620         var->assign_hook = assign_hook;
6621         var->show_hook = show_hook;
6622         define_custom_variable(&var->gen);
6623 }
6624
6625 void
6626 DefineCustomEnumVariable(const char *name,
6627                                                  const char *short_desc,
6628                                                  const char *long_desc,
6629                                                  int *valueAddr,
6630                                                  int bootValue,
6631                                                  const struct config_enum_entry * options,
6632                                                  GucContext context,
6633                                                  int flags,
6634                                                  GucEnumCheckHook check_hook,
6635                                                  GucEnumAssignHook assign_hook,
6636                                                  GucShowHook show_hook)
6637 {
6638         struct config_enum *var;
6639
6640         var = (struct config_enum *)
6641                 init_custom_variable(name, short_desc, long_desc, context, flags,
6642                                                          PGC_ENUM, sizeof(struct config_enum));
6643         var->variable = valueAddr;
6644         var->boot_val = bootValue;
6645         var->reset_val = bootValue;
6646         var->options = options;
6647         var->check_hook = check_hook;
6648         var->assign_hook = assign_hook;
6649         var->show_hook = show_hook;
6650         define_custom_variable(&var->gen);
6651 }
6652
6653 void
6654 EmitWarningsOnPlaceholders(const char *className)
6655 {
6656         int                     classLen = strlen(className);
6657         int                     i;
6658
6659         for (i = 0; i < num_guc_variables; i++)
6660         {
6661                 struct config_generic *var = guc_variables[i];
6662
6663                 if ((var->flags & GUC_CUSTOM_PLACEHOLDER) != 0 &&
6664                         strncmp(className, var->name, classLen) == 0 &&
6665                         var->name[classLen] == GUC_QUALIFIER_SEPARATOR)
6666                 {
6667                         ereport(WARNING,
6668                                         (errcode(ERRCODE_UNDEFINED_OBJECT),
6669                                          errmsg("unrecognized configuration parameter \"%s\"",
6670                                                         var->name)));
6671                 }
6672         }
6673 }
6674
6675
6676 /*
6677  * SHOW command
6678  */
6679 void
6680 GetPGVariable(const char *name, DestReceiver *dest)
6681 {
6682         if (guc_name_compare(name, "all") == 0)
6683                 ShowAllGUCConfig(dest);
6684         else
6685                 ShowGUCConfigOption(name, dest);
6686 }
6687
6688 TupleDesc
6689 GetPGVariableResultDesc(const char *name)
6690 {
6691         TupleDesc       tupdesc;
6692
6693         if (guc_name_compare(name, "all") == 0)
6694         {
6695                 /* need a tuple descriptor representing three TEXT columns */
6696                 tupdesc = CreateTemplateTupleDesc(3, false);
6697                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
6698                                                    TEXTOID, -1, 0);
6699                 TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
6700                                                    TEXTOID, -1, 0);
6701                 TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
6702                                                    TEXTOID, -1, 0);
6703         }
6704         else
6705         {
6706                 const char *varname;
6707
6708                 /* Get the canonical spelling of name */
6709                 (void) GetConfigOptionByName(name, &varname);
6710
6711                 /* need a tuple descriptor representing a single TEXT column */
6712                 tupdesc = CreateTemplateTupleDesc(1, false);
6713                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, varname,
6714                                                    TEXTOID, -1, 0);
6715         }
6716         return tupdesc;
6717 }
6718
6719
6720 /*
6721  * SHOW command
6722  */
6723 static void
6724 ShowGUCConfigOption(const char *name, DestReceiver *dest)
6725 {
6726         TupOutputState *tstate;
6727         TupleDesc       tupdesc;
6728         const char *varname;
6729         char       *value;
6730
6731         /* Get the value and canonical spelling of name */
6732         value = GetConfigOptionByName(name, &varname);
6733
6734         /* need a tuple descriptor representing a single TEXT column */
6735         tupdesc = CreateTemplateTupleDesc(1, false);
6736         TupleDescInitEntry(tupdesc, (AttrNumber) 1, varname,
6737                                            TEXTOID, -1, 0);
6738
6739         /* prepare for projection of tuples */
6740         tstate = begin_tup_output_tupdesc(dest, tupdesc);
6741
6742         /* Send it */
6743         do_text_output_oneline(tstate, value);
6744
6745         end_tup_output(tstate);
6746 }
6747
6748 /*
6749  * SHOW ALL command
6750  */
6751 static void
6752 ShowAllGUCConfig(DestReceiver *dest)
6753 {
6754         bool            am_superuser = superuser();
6755         int                     i;
6756         TupOutputState *tstate;
6757         TupleDesc       tupdesc;
6758         Datum           values[3];
6759         bool            isnull[3] = {false, false, false};
6760
6761         /* need a tuple descriptor representing three TEXT columns */
6762         tupdesc = CreateTemplateTupleDesc(3, false);
6763         TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
6764                                            TEXTOID, -1, 0);
6765         TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
6766                                            TEXTOID, -1, 0);
6767         TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
6768                                            TEXTOID, -1, 0);
6769
6770         /* prepare for projection of tuples */
6771         tstate = begin_tup_output_tupdesc(dest, tupdesc);
6772
6773         for (i = 0; i < num_guc_variables; i++)
6774         {
6775                 struct config_generic *conf = guc_variables[i];
6776                 char       *setting;
6777
6778                 if ((conf->flags & GUC_NO_SHOW_ALL) ||
6779                         ((conf->flags & GUC_SUPERUSER_ONLY) && !am_superuser))
6780                         continue;
6781
6782                 /* assign to the values array */
6783                 values[0] = PointerGetDatum(cstring_to_text(conf->name));
6784
6785                 setting = _ShowOption(conf, true);
6786                 if (setting)
6787                 {
6788                         values[1] = PointerGetDatum(cstring_to_text(setting));
6789                         isnull[1] = false;
6790                 }
6791                 else
6792                 {
6793                         values[1] = PointerGetDatum(NULL);
6794                         isnull[1] = true;
6795                 }
6796
6797                 values[2] = PointerGetDatum(cstring_to_text(conf->short_desc));
6798
6799                 /* send it to dest */
6800                 do_tup_output(tstate, values, isnull);
6801
6802                 /* clean up */
6803                 pfree(DatumGetPointer(values[0]));
6804                 if (setting)
6805                 {
6806                         pfree(setting);
6807                         pfree(DatumGetPointer(values[1]));
6808                 }
6809                 pfree(DatumGetPointer(values[2]));
6810         }
6811
6812         end_tup_output(tstate);
6813 }
6814
6815 /*
6816  * Return GUC variable value by name; optionally return canonical
6817  * form of name.  Return value is palloc'd.
6818  */
6819 char *
6820 GetConfigOptionByName(const char *name, const char **varname)
6821 {
6822         struct config_generic *record;
6823
6824         record = find_option(name, false, ERROR);
6825         if (record == NULL)
6826                 ereport(ERROR,
6827                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
6828                            errmsg("unrecognized configuration parameter \"%s\"", name)));
6829         if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
6830                 ereport(ERROR,
6831                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
6832                                  errmsg("must be superuser to examine \"%s\"", name)));
6833
6834         if (varname)
6835                 *varname = record->name;
6836
6837         return _ShowOption(record, true);
6838 }
6839
6840 /*
6841  * Return GUC variable value by variable number; optionally return canonical
6842  * form of name.  Return value is palloc'd.
6843  */
6844 void
6845 GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
6846 {
6847         char            buffer[256];
6848         struct config_generic *conf;
6849
6850         /* check requested variable number valid */
6851         Assert((varnum >= 0) && (varnum < num_guc_variables));
6852
6853         conf = guc_variables[varnum];
6854
6855         if (noshow)
6856         {
6857                 if ((conf->flags & GUC_NO_SHOW_ALL) ||
6858                         ((conf->flags & GUC_SUPERUSER_ONLY) && !superuser()))
6859                         *noshow = true;
6860                 else
6861                         *noshow = false;
6862         }
6863
6864         /* first get the generic attributes */
6865
6866         /* name */
6867         values[0] = conf->name;
6868
6869         /* setting : use _ShowOption in order to avoid duplicating the logic */
6870         values[1] = _ShowOption(conf, false);
6871
6872         /* unit */
6873         if (conf->vartype == PGC_INT)
6874         {
6875                 static char buf[8];
6876
6877                 switch (conf->flags & (GUC_UNIT_MEMORY | GUC_UNIT_TIME))
6878                 {
6879                         case GUC_UNIT_KB:
6880                                 values[2] = "kB";
6881                                 break;
6882                         case GUC_UNIT_BLOCKS:
6883                                 snprintf(buf, sizeof(buf), "%dkB", BLCKSZ / 1024);
6884                                 values[2] = buf;
6885                                 break;
6886                         case GUC_UNIT_XBLOCKS:
6887                                 snprintf(buf, sizeof(buf), "%dkB", XLOG_BLCKSZ / 1024);
6888                                 values[2] = buf;
6889                                 break;
6890                         case GUC_UNIT_MS:
6891                                 values[2] = "ms";
6892                                 break;
6893                         case GUC_UNIT_S:
6894                                 values[2] = "s";
6895                                 break;
6896                         case GUC_UNIT_MIN:
6897                                 values[2] = "min";
6898                                 break;
6899                         default:
6900                                 values[2] = "";
6901                                 break;
6902                 }
6903         }
6904         else
6905                 values[2] = NULL;
6906
6907         /* group */
6908         values[3] = config_group_names[conf->group];
6909
6910         /* short_desc */
6911         values[4] = conf->short_desc;
6912
6913         /* extra_desc */
6914         values[5] = conf->long_desc;
6915
6916         /* context */
6917         values[6] = GucContext_Names[conf->context];
6918
6919         /* vartype */
6920         values[7] = config_type_names[conf->vartype];
6921
6922         /* source */
6923         values[8] = GucSource_Names[conf->source];
6924
6925         /* now get the type specifc attributes */
6926         switch (conf->vartype)
6927         {
6928                 case PGC_BOOL:
6929                         {
6930                                 struct config_bool *lconf = (struct config_bool *) conf;
6931
6932                                 /* min_val */
6933                                 values[9] = NULL;
6934
6935                                 /* max_val */
6936                                 values[10] = NULL;
6937
6938                                 /* enumvals */
6939                                 values[11] = NULL;
6940
6941                                 /* boot_val */
6942                                 values[12] = pstrdup(lconf->boot_val ? "on" : "off");
6943
6944                                 /* reset_val */
6945                                 values[13] = pstrdup(lconf->reset_val ? "on" : "off");
6946                         }
6947                         break;
6948
6949                 case PGC_INT:
6950                         {
6951                                 struct config_int *lconf = (struct config_int *) conf;
6952
6953                                 /* min_val */
6954                                 snprintf(buffer, sizeof(buffer), "%d", lconf->min);
6955                                 values[9] = pstrdup(buffer);
6956
6957                                 /* max_val */
6958                                 snprintf(buffer, sizeof(buffer), "%d", lconf->max);
6959                                 values[10] = pstrdup(buffer);
6960
6961                                 /* enumvals */
6962                                 values[11] = NULL;
6963
6964                                 /* boot_val */
6965                                 snprintf(buffer, sizeof(buffer), "%d", lconf->boot_val);
6966                                 values[12] = pstrdup(buffer);
6967
6968                                 /* reset_val */
6969                                 snprintf(buffer, sizeof(buffer), "%d", lconf->reset_val);
6970                                 values[13] = pstrdup(buffer);
6971                         }
6972                         break;
6973
6974                 case PGC_REAL:
6975                         {
6976                                 struct config_real *lconf = (struct config_real *) conf;
6977
6978                                 /* min_val */
6979                                 snprintf(buffer, sizeof(buffer), "%g", lconf->min);
6980                                 values[9] = pstrdup(buffer);
6981
6982                                 /* max_val */
6983                                 snprintf(buffer, sizeof(buffer), "%g", lconf->max);
6984                                 values[10] = pstrdup(buffer);
6985
6986                                 /* enumvals */
6987                                 values[11] = NULL;
6988
6989                                 /* boot_val */
6990                                 snprintf(buffer, sizeof(buffer), "%g", lconf->boot_val);
6991                                 values[12] = pstrdup(buffer);
6992
6993                                 /* reset_val */
6994                                 snprintf(buffer, sizeof(buffer), "%g", lconf->reset_val);
6995                                 values[13] = pstrdup(buffer);
6996                         }
6997                         break;
6998
6999                 case PGC_STRING:
7000                         {
7001                                 struct config_string *lconf = (struct config_string *) conf;
7002
7003                                 /* min_val */
7004                                 values[9] = NULL;
7005
7006                                 /* max_val */
7007                                 values[10] = NULL;
7008
7009                                 /* enumvals */
7010                                 values[11] = NULL;
7011
7012                                 /* boot_val */
7013                                 if (lconf->boot_val == NULL)
7014                                         values[12] = NULL;
7015                                 else
7016                                         values[12] = pstrdup(lconf->boot_val);
7017
7018                                 /* reset_val */
7019                                 if (lconf->reset_val == NULL)
7020                                         values[13] = NULL;
7021                                 else
7022                                         values[13] = pstrdup(lconf->reset_val);
7023                         }
7024                         break;
7025
7026                 case PGC_ENUM:
7027                         {
7028                                 struct config_enum *lconf = (struct config_enum *) conf;
7029
7030                                 /* min_val */
7031                                 values[9] = NULL;
7032
7033                                 /* max_val */
7034                                 values[10] = NULL;
7035
7036                                 /* enumvals */
7037
7038                                 /*
7039                                  * NOTE! enumvals with double quotes in them are not
7040                                  * supported!
7041                                  */
7042                                 values[11] = config_enum_get_options((struct config_enum *) conf,
7043                                                                                                          "{\"", "\"}", "\",\"");
7044
7045                                 /* boot_val */
7046                                 values[12] = pstrdup(config_enum_lookup_by_value(lconf,
7047                                                                                                                    lconf->boot_val));
7048
7049                                 /* reset_val */
7050                                 values[13] = pstrdup(config_enum_lookup_by_value(lconf,
7051                                                                                                                   lconf->reset_val));
7052                         }
7053                         break;
7054
7055                 default:
7056                         {
7057                                 /*
7058                                  * should never get here, but in case we do, set 'em to NULL
7059                                  */
7060
7061                                 /* min_val */
7062                                 values[9] = NULL;
7063
7064                                 /* max_val */
7065                                 values[10] = NULL;
7066
7067                                 /* enumvals */
7068                                 values[11] = NULL;
7069
7070                                 /* boot_val */
7071                                 values[12] = NULL;
7072
7073                                 /* reset_val */
7074                                 values[13] = NULL;
7075                         }
7076                         break;
7077         }
7078
7079         /*
7080          * If the setting came from a config file, set the source location. For
7081          * security reasons, we don't show source file/line number for
7082          * non-superusers.
7083          */
7084         if (conf->source == PGC_S_FILE && superuser())
7085         {
7086                 values[14] = conf->sourcefile;
7087                 snprintf(buffer, sizeof(buffer), "%d", conf->sourceline);
7088                 values[15] = pstrdup(buffer);
7089         }
7090         else
7091         {
7092                 values[14] = NULL;
7093                 values[15] = NULL;
7094         }
7095 }
7096
7097 /*
7098  * Return the total number of GUC variables
7099  */
7100 int
7101 GetNumConfigOptions(void)
7102 {
7103         return num_guc_variables;
7104 }
7105
7106 /*
7107  * show_config_by_name - equiv to SHOW X command but implemented as
7108  * a function.
7109  */
7110 Datum
7111 show_config_by_name(PG_FUNCTION_ARGS)
7112 {
7113         char       *varname;
7114         char       *varval;
7115
7116         /* Get the GUC variable name */
7117         varname = TextDatumGetCString(PG_GETARG_DATUM(0));
7118
7119         /* Get the value */
7120         varval = GetConfigOptionByName(varname, NULL);
7121
7122         /* Convert to text */
7123         PG_RETURN_TEXT_P(cstring_to_text(varval));
7124 }
7125
7126 /*
7127  * show_all_settings - equiv to SHOW ALL command but implemented as
7128  * a Table Function.
7129  */
7130 #define NUM_PG_SETTINGS_ATTS    16
7131
7132 Datum
7133 show_all_settings(PG_FUNCTION_ARGS)
7134 {
7135         FuncCallContext *funcctx;
7136         TupleDesc       tupdesc;
7137         int                     call_cntr;
7138         int                     max_calls;
7139         AttInMetadata *attinmeta;
7140         MemoryContext oldcontext;
7141
7142         /* stuff done only on the first call of the function */
7143         if (SRF_IS_FIRSTCALL())
7144         {
7145                 /* create a function context for cross-call persistence */
7146                 funcctx = SRF_FIRSTCALL_INIT();
7147
7148                 /*
7149                  * switch to memory context appropriate for multiple function calls
7150                  */
7151                 oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
7152
7153                 /*
7154                  * need a tuple descriptor representing NUM_PG_SETTINGS_ATTS columns
7155                  * of the appropriate types
7156                  */
7157                 tupdesc = CreateTemplateTupleDesc(NUM_PG_SETTINGS_ATTS, false);
7158                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
7159                                                    TEXTOID, -1, 0);
7160                 TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
7161                                                    TEXTOID, -1, 0);
7162                 TupleDescInitEntry(tupdesc, (AttrNumber) 3, "unit",
7163                                                    TEXTOID, -1, 0);
7164                 TupleDescInitEntry(tupdesc, (AttrNumber) 4, "category",
7165                                                    TEXTOID, -1, 0);
7166                 TupleDescInitEntry(tupdesc, (AttrNumber) 5, "short_desc",
7167                                                    TEXTOID, -1, 0);
7168                 TupleDescInitEntry(tupdesc, (AttrNumber) 6, "extra_desc",
7169                                                    TEXTOID, -1, 0);
7170                 TupleDescInitEntry(tupdesc, (AttrNumber) 7, "context",
7171                                                    TEXTOID, -1, 0);
7172                 TupleDescInitEntry(tupdesc, (AttrNumber) 8, "vartype",
7173                                                    TEXTOID, -1, 0);
7174                 TupleDescInitEntry(tupdesc, (AttrNumber) 9, "source",
7175                                                    TEXTOID, -1, 0);
7176                 TupleDescInitEntry(tupdesc, (AttrNumber) 10, "min_val",
7177                                                    TEXTOID, -1, 0);
7178                 TupleDescInitEntry(tupdesc, (AttrNumber) 11, "max_val",
7179                                                    TEXTOID, -1, 0);
7180                 TupleDescInitEntry(tupdesc, (AttrNumber) 12, "enumvals",
7181                                                    TEXTARRAYOID, -1, 0);
7182                 TupleDescInitEntry(tupdesc, (AttrNumber) 13, "boot_val",
7183                                                    TEXTOID, -1, 0);
7184                 TupleDescInitEntry(tupdesc, (AttrNumber) 14, "reset_val",
7185                                                    TEXTOID, -1, 0);
7186                 TupleDescInitEntry(tupdesc, (AttrNumber) 15, "sourcefile",
7187                                                    TEXTOID, -1, 0);
7188                 TupleDescInitEntry(tupdesc, (AttrNumber) 16, "sourceline",
7189                                                    INT4OID, -1, 0);
7190
7191                 /*
7192                  * Generate attribute metadata needed later to produce tuples from raw
7193                  * C strings
7194                  */
7195                 attinmeta = TupleDescGetAttInMetadata(tupdesc);
7196                 funcctx->attinmeta = attinmeta;
7197
7198                 /* total number of tuples to be returned */
7199                 funcctx->max_calls = GetNumConfigOptions();
7200
7201                 MemoryContextSwitchTo(oldcontext);
7202         }
7203
7204         /* stuff done on every call of the function */
7205         funcctx = SRF_PERCALL_SETUP();
7206
7207         call_cntr = funcctx->call_cntr;
7208         max_calls = funcctx->max_calls;
7209         attinmeta = funcctx->attinmeta;
7210
7211         if (call_cntr < max_calls)      /* do when there is more left to send */
7212         {
7213                 char       *values[NUM_PG_SETTINGS_ATTS];
7214                 bool            noshow;
7215                 HeapTuple       tuple;
7216                 Datum           result;
7217
7218                 /*
7219                  * Get the next visible GUC variable name and value
7220                  */
7221                 do
7222                 {
7223                         GetConfigOptionByNum(call_cntr, (const char **) values, &noshow);
7224                         if (noshow)
7225                         {
7226                                 /* bump the counter and get the next config setting */
7227                                 call_cntr = ++funcctx->call_cntr;
7228
7229                                 /* make sure we haven't gone too far now */
7230                                 if (call_cntr >= max_calls)
7231                                         SRF_RETURN_DONE(funcctx);
7232                         }
7233                 } while (noshow);
7234
7235                 /* build a tuple */
7236                 tuple = BuildTupleFromCStrings(attinmeta, values);
7237
7238                 /* make the tuple into a datum */
7239                 result = HeapTupleGetDatum(tuple);
7240
7241                 SRF_RETURN_NEXT(funcctx, result);
7242         }
7243         else
7244         {
7245                 /* do when there is no more left */
7246                 SRF_RETURN_DONE(funcctx);
7247         }
7248 }
7249
7250 static char *
7251 _ShowOption(struct config_generic * record, bool use_units)
7252 {
7253         char            buffer[256];
7254         const char *val;
7255
7256         switch (record->vartype)
7257         {
7258                 case PGC_BOOL:
7259                         {
7260                                 struct config_bool *conf = (struct config_bool *) record;
7261
7262                                 if (conf->show_hook)
7263                                         val = (*conf->show_hook) ();
7264                                 else
7265                                         val = *conf->variable ? "on" : "off";
7266                         }
7267                         break;
7268
7269                 case PGC_INT:
7270                         {
7271                                 struct config_int *conf = (struct config_int *) record;
7272
7273                                 if (conf->show_hook)
7274                                         val = (*conf->show_hook) ();
7275                                 else
7276                                 {
7277                                         /*
7278                                          * Use int64 arithmetic to avoid overflows in units
7279                                          * conversion.
7280                                          */
7281                                         int64           result = *conf->variable;
7282                                         const char *unit;
7283
7284                                         if (use_units && result > 0 &&
7285                                                 (record->flags & GUC_UNIT_MEMORY))
7286                                         {
7287                                                 switch (record->flags & GUC_UNIT_MEMORY)
7288                                                 {
7289                                                         case GUC_UNIT_BLOCKS:
7290                                                                 result *= BLCKSZ / 1024;
7291                                                                 break;
7292                                                         case GUC_UNIT_XBLOCKS:
7293                                                                 result *= XLOG_BLCKSZ / 1024;
7294                                                                 break;
7295                                                 }
7296
7297                                                 if (result % KB_PER_GB == 0)
7298                                                 {
7299                                                         result /= KB_PER_GB;
7300                                                         unit = "GB";
7301                                                 }
7302                                                 else if (result % KB_PER_MB == 0)
7303                                                 {
7304                                                         result /= KB_PER_MB;
7305                                                         unit = "MB";
7306                                                 }
7307                                                 else
7308                                                 {
7309                                                         unit = "kB";
7310                                                 }
7311                                         }
7312                                         else if (use_units && result > 0 &&
7313                                                          (record->flags & GUC_UNIT_TIME))
7314                                         {
7315                                                 switch (record->flags & GUC_UNIT_TIME)
7316                                                 {
7317                                                         case GUC_UNIT_S:
7318                                                                 result *= MS_PER_S;
7319                                                                 break;
7320                                                         case GUC_UNIT_MIN:
7321                                                                 result *= MS_PER_MIN;
7322                                                                 break;
7323                                                 }
7324
7325                                                 if (result % MS_PER_D == 0)
7326                                                 {
7327                                                         result /= MS_PER_D;
7328                                                         unit = "d";
7329                                                 }
7330                                                 else if (result % MS_PER_H == 0)
7331                                                 {
7332                                                         result /= MS_PER_H;
7333                                                         unit = "h";
7334                                                 }
7335                                                 else if (result % MS_PER_MIN == 0)
7336                                                 {
7337                                                         result /= MS_PER_MIN;
7338                                                         unit = "min";
7339                                                 }
7340                                                 else if (result % MS_PER_S == 0)
7341                                                 {
7342                                                         result /= MS_PER_S;
7343                                                         unit = "s";
7344                                                 }
7345                                                 else
7346                                                 {
7347                                                         unit = "ms";
7348                                                 }
7349                                         }
7350                                         else
7351                                                 unit = "";
7352
7353                                         snprintf(buffer, sizeof(buffer), INT64_FORMAT "%s",
7354                                                          result, unit);
7355                                         val = buffer;
7356                                 }
7357                         }
7358                         break;
7359
7360                 case PGC_REAL:
7361                         {
7362                                 struct config_real *conf = (struct config_real *) record;
7363
7364                                 if (conf->show_hook)
7365                                         val = (*conf->show_hook) ();
7366                                 else
7367                                 {
7368                                         snprintf(buffer, sizeof(buffer), "%g",
7369                                                          *conf->variable);
7370                                         val = buffer;
7371                                 }
7372                         }
7373                         break;
7374
7375                 case PGC_STRING:
7376                         {
7377                                 struct config_string *conf = (struct config_string *) record;
7378
7379                                 if (conf->show_hook)
7380                                         val = (*conf->show_hook) ();
7381                                 else if (*conf->variable && **conf->variable)
7382                                         val = *conf->variable;
7383                                 else
7384                                         val = "";
7385                         }
7386                         break;
7387
7388                 case PGC_ENUM:
7389                         {
7390                                 struct config_enum *conf = (struct config_enum *) record;
7391
7392                                 if (conf->show_hook)
7393                                         val = (*conf->show_hook) ();
7394                                 else
7395                                         val = config_enum_lookup_by_value(conf, *conf->variable);
7396                         }
7397                         break;
7398
7399                 default:
7400                         /* just to keep compiler quiet */
7401                         val = "???";
7402                         break;
7403         }
7404
7405         return pstrdup(val);
7406 }
7407
7408
7409 #ifdef EXEC_BACKEND
7410
7411 /*
7412  *      These routines dump out all non-default GUC options into a binary
7413  *      file that is read by all exec'ed backends.  The format is:
7414  *
7415  *              variable name, string, null terminated
7416  *              variable value, string, null terminated
7417  *              variable sourcefile, string, null terminated (empty if none)
7418  *              variable sourceline, integer
7419  *              variable source, integer
7420  *              variable scontext, integer
7421  */
7422 static void
7423 write_one_nondefault_variable(FILE *fp, struct config_generic * gconf)
7424 {
7425         if (gconf->source == PGC_S_DEFAULT)
7426                 return;
7427
7428         fprintf(fp, "%s", gconf->name);
7429         fputc(0, fp);
7430
7431         switch (gconf->vartype)
7432         {
7433                 case PGC_BOOL:
7434                         {
7435                                 struct config_bool *conf = (struct config_bool *) gconf;
7436
7437                                 if (*conf->variable)
7438                                         fprintf(fp, "true");
7439                                 else
7440                                         fprintf(fp, "false");
7441                         }
7442                         break;
7443
7444                 case PGC_INT:
7445                         {
7446                                 struct config_int *conf = (struct config_int *) gconf;
7447
7448                                 fprintf(fp, "%d", *conf->variable);
7449                         }
7450                         break;
7451
7452                 case PGC_REAL:
7453                         {
7454                                 struct config_real *conf = (struct config_real *) gconf;
7455
7456                                 fprintf(fp, "%.17g", *conf->variable);
7457                         }
7458                         break;
7459
7460                 case PGC_STRING:
7461                         {
7462                                 struct config_string *conf = (struct config_string *) gconf;
7463
7464                                 fprintf(fp, "%s", *conf->variable);
7465                         }
7466                         break;
7467
7468                 case PGC_ENUM:
7469                         {
7470                                 struct config_enum *conf = (struct config_enum *) gconf;
7471
7472                                 fprintf(fp, "%s",
7473                                                 config_enum_lookup_by_value(conf, *conf->variable));
7474                         }
7475                         break;
7476         }
7477
7478         fputc(0, fp);
7479
7480         if (gconf->sourcefile)
7481                 fprintf(fp, "%s", gconf->sourcefile);
7482         fputc(0, fp);
7483
7484         fwrite(&gconf->sourceline, 1, sizeof(gconf->sourceline), fp);
7485         fwrite(&gconf->source, 1, sizeof(gconf->source), fp);
7486         fwrite(&gconf->scontext, 1, sizeof(gconf->scontext), fp);
7487 }
7488
7489 void
7490 write_nondefault_variables(GucContext context)
7491 {
7492         int                     elevel;
7493         FILE       *fp;
7494         int                     i;
7495
7496         Assert(context == PGC_POSTMASTER || context == PGC_SIGHUP);
7497
7498         elevel = (context == PGC_SIGHUP) ? LOG : ERROR;
7499
7500         /*
7501          * Open file
7502          */
7503         fp = AllocateFile(CONFIG_EXEC_PARAMS_NEW, "w");
7504         if (!fp)
7505         {
7506                 ereport(elevel,
7507                                 (errcode_for_file_access(),
7508                                  errmsg("could not write to file \"%s\": %m",
7509                                                 CONFIG_EXEC_PARAMS_NEW)));
7510                 return;
7511         }
7512
7513         for (i = 0; i < num_guc_variables; i++)
7514         {
7515                 write_one_nondefault_variable(fp, guc_variables[i]);
7516         }
7517
7518         if (FreeFile(fp))
7519         {
7520                 ereport(elevel,
7521                                 (errcode_for_file_access(),
7522                                  errmsg("could not write to file \"%s\": %m",
7523                                                 CONFIG_EXEC_PARAMS_NEW)));
7524                 return;
7525         }
7526
7527         /*
7528          * Put new file in place.  This could delay on Win32, but we don't hold
7529          * any exclusive locks.
7530          */
7531         rename(CONFIG_EXEC_PARAMS_NEW, CONFIG_EXEC_PARAMS);
7532 }
7533
7534
7535 /*
7536  *      Read string, including null byte from file
7537  *
7538  *      Return NULL on EOF and nothing read
7539  */
7540 static char *
7541 read_string_with_null(FILE *fp)
7542 {
7543         int                     i = 0,
7544                                 ch,
7545                                 maxlen = 256;
7546         char       *str = NULL;
7547
7548         do
7549         {
7550                 if ((ch = fgetc(fp)) == EOF)
7551                 {
7552                         if (i == 0)
7553                                 return NULL;
7554                         else
7555                                 elog(FATAL, "invalid format of exec config params file");
7556                 }
7557                 if (i == 0)
7558                         str = guc_malloc(FATAL, maxlen);
7559                 else if (i == maxlen)
7560                         str = guc_realloc(FATAL, str, maxlen *= 2);
7561                 str[i++] = ch;
7562         } while (ch != 0);
7563
7564         return str;
7565 }
7566
7567
7568 /*
7569  *      This routine loads a previous postmaster dump of its non-default
7570  *      settings.
7571  */
7572 void
7573 read_nondefault_variables(void)
7574 {
7575         FILE       *fp;
7576         char       *varname,
7577                            *varvalue,
7578                            *varsourcefile;
7579         int                     varsourceline;
7580         GucSource       varsource;
7581         GucContext      varscontext;
7582
7583         /*
7584          * Open file
7585          */
7586         fp = AllocateFile(CONFIG_EXEC_PARAMS, "r");
7587         if (!fp)
7588         {
7589                 /* File not found is fine */
7590                 if (errno != ENOENT)
7591                         ereport(FATAL,
7592                                         (errcode_for_file_access(),
7593                                          errmsg("could not read from file \"%s\": %m",
7594                                                         CONFIG_EXEC_PARAMS)));
7595                 return;
7596         }
7597
7598         for (;;)
7599         {
7600                 struct config_generic *record;
7601
7602                 if ((varname = read_string_with_null(fp)) == NULL)
7603                         break;
7604
7605                 if ((record = find_option(varname, true, FATAL)) == NULL)
7606                         elog(FATAL, "failed to locate variable \"%s\" in exec config params file", varname);
7607
7608                 if ((varvalue = read_string_with_null(fp)) == NULL)
7609                         elog(FATAL, "invalid format of exec config params file");
7610                 if ((varsourcefile = read_string_with_null(fp)) == NULL)
7611                         elog(FATAL, "invalid format of exec config params file");
7612                 if (fread(&varsourceline, 1, sizeof(varsourceline), fp) != sizeof(varsourceline))
7613                         elog(FATAL, "invalid format of exec config params file");
7614                 if (fread(&varsource, 1, sizeof(varsource), fp) != sizeof(varsource))
7615                         elog(FATAL, "invalid format of exec config params file");
7616                 if (fread(&varscontext, 1, sizeof(varscontext), fp) != sizeof(varscontext))
7617                         elog(FATAL, "invalid format of exec config params file");
7618
7619                 (void) set_config_option(varname, varvalue,
7620                                                                  varscontext, varsource,
7621                                                                  GUC_ACTION_SET, true, 0);
7622                 if (varsourcefile[0])
7623                         set_config_sourcefile(varname, varsourcefile, varsourceline);
7624
7625                 free(varname);
7626                 free(varvalue);
7627                 free(varsourcefile);
7628         }
7629
7630         FreeFile(fp);
7631 }
7632 #endif   /* EXEC_BACKEND */
7633
7634
7635 /*
7636  * A little "long argument" simulation, although not quite GNU
7637  * compliant. Takes a string of the form "some-option=some value" and
7638  * returns name = "some_option" and value = "some value" in malloc'ed
7639  * storage. Note that '-' is converted to '_' in the option name. If
7640  * there is no '=' in the input string then value will be NULL.
7641  */
7642 void
7643 ParseLongOption(const char *string, char **name, char **value)
7644 {
7645         size_t          equal_pos;
7646         char       *cp;
7647
7648         AssertArg(string);
7649         AssertArg(name);
7650         AssertArg(value);
7651
7652         equal_pos = strcspn(string, "=");
7653
7654         if (string[equal_pos] == '=')
7655         {
7656                 *name = guc_malloc(FATAL, equal_pos + 1);
7657                 strlcpy(*name, string, equal_pos + 1);
7658
7659                 *value = guc_strdup(FATAL, &string[equal_pos + 1]);
7660         }
7661         else
7662         {
7663                 /* no equal sign in string */
7664                 *name = guc_strdup(FATAL, string);
7665                 *value = NULL;
7666         }
7667
7668         for (cp = *name; *cp; cp++)
7669                 if (*cp == '-')
7670                         *cp = '_';
7671 }
7672
7673
7674 /*
7675  * Handle options fetched from pg_db_role_setting.setconfig,
7676  * pg_proc.proconfig, etc.      Caller must specify proper context/source/action.
7677  *
7678  * The array parameter must be an array of TEXT (it must not be NULL).
7679  */
7680 void
7681 ProcessGUCArray(ArrayType *array,
7682                                 GucContext context, GucSource source, GucAction action)
7683 {
7684         int                     i;
7685
7686         Assert(array != NULL);
7687         Assert(ARR_ELEMTYPE(array) == TEXTOID);
7688         Assert(ARR_NDIM(array) == 1);
7689         Assert(ARR_LBOUND(array)[0] == 1);
7690
7691         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7692         {
7693                 Datum           d;
7694                 bool            isnull;
7695                 char       *s;
7696                 char       *name;
7697                 char       *value;
7698
7699                 d = array_ref(array, 1, &i,
7700                                           -1 /* varlenarray */ ,
7701                                           -1 /* TEXT's typlen */ ,
7702                                           false /* TEXT's typbyval */ ,
7703                                           'i' /* TEXT's typalign */ ,
7704                                           &isnull);
7705
7706                 if (isnull)
7707                         continue;
7708
7709                 s = TextDatumGetCString(d);
7710
7711                 ParseLongOption(s, &name, &value);
7712                 if (!value)
7713                 {
7714                         ereport(WARNING,
7715                                         (errcode(ERRCODE_SYNTAX_ERROR),
7716                                          errmsg("could not parse setting for parameter \"%s\"",
7717                                                         name)));
7718                         free(name);
7719                         continue;
7720                 }
7721
7722                 (void) set_config_option(name, value,
7723                                                                  context, source,
7724                                                                  action, true, 0);
7725
7726                 free(name);
7727                 if (value)
7728                         free(value);
7729                 pfree(s);
7730         }
7731 }
7732
7733
7734 /*
7735  * Add an entry to an option array.  The array parameter may be NULL
7736  * to indicate the current table entry is NULL.
7737  */
7738 ArrayType *
7739 GUCArrayAdd(ArrayType *array, const char *name, const char *value)
7740 {
7741         struct config_generic *record;
7742         Datum           datum;
7743         char       *newval;
7744         ArrayType  *a;
7745
7746         Assert(name);
7747         Assert(value);
7748
7749         /* test if the option is valid and we're allowed to set it */
7750         (void) validate_option_array_item(name, value, false);
7751
7752         /* normalize name (converts obsolete GUC names to modern spellings) */
7753         record = find_option(name, false, WARNING);
7754         if (record)
7755                 name = record->name;
7756
7757         /* build new item for array */
7758         newval = palloc(strlen(name) + 1 + strlen(value) + 1);
7759         sprintf(newval, "%s=%s", name, value);
7760         datum = CStringGetTextDatum(newval);
7761
7762         if (array)
7763         {
7764                 int                     index;
7765                 bool            isnull;
7766                 int                     i;
7767
7768                 Assert(ARR_ELEMTYPE(array) == TEXTOID);
7769                 Assert(ARR_NDIM(array) == 1);
7770                 Assert(ARR_LBOUND(array)[0] == 1);
7771
7772                 index = ARR_DIMS(array)[0] + 1; /* add after end */
7773
7774                 for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7775                 {
7776                         Datum           d;
7777                         char       *current;
7778
7779                         d = array_ref(array, 1, &i,
7780                                                   -1 /* varlenarray */ ,
7781                                                   -1 /* TEXT's typlen */ ,
7782                                                   false /* TEXT's typbyval */ ,
7783                                                   'i' /* TEXT's typalign */ ,
7784                                                   &isnull);
7785                         if (isnull)
7786                                 continue;
7787                         current = TextDatumGetCString(d);
7788
7789                         /* check for match up through and including '=' */
7790                         if (strncmp(current, newval, strlen(name) + 1) == 0)
7791                         {
7792                                 index = i;
7793                                 break;
7794                         }
7795                 }
7796
7797                 a = array_set(array, 1, &index,
7798                                           datum,
7799                                           false,
7800                                           -1 /* varlena array */ ,
7801                                           -1 /* TEXT's typlen */ ,
7802                                           false /* TEXT's typbyval */ ,
7803                                           'i' /* TEXT's typalign */ );
7804         }
7805         else
7806                 a = construct_array(&datum, 1,
7807                                                         TEXTOID,
7808                                                         -1, false, 'i');
7809
7810         return a;
7811 }
7812
7813
7814 /*
7815  * Delete an entry from an option array.  The array parameter may be NULL
7816  * to indicate the current table entry is NULL.  Also, if the return value
7817  * is NULL then a null should be stored.
7818  */
7819 ArrayType *
7820 GUCArrayDelete(ArrayType *array, const char *name)
7821 {
7822         struct config_generic *record;
7823         ArrayType  *newarray;
7824         int                     i;
7825         int                     index;
7826
7827         Assert(name);
7828
7829         /* test if the option is valid and we're allowed to set it */
7830         (void) validate_option_array_item(name, NULL, false);
7831
7832         /* normalize name (converts obsolete GUC names to modern spellings) */
7833         record = find_option(name, false, WARNING);
7834         if (record)
7835                 name = record->name;
7836
7837         /* if array is currently null, then surely nothing to delete */
7838         if (!array)
7839                 return NULL;
7840
7841         newarray = NULL;
7842         index = 1;
7843
7844         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7845         {
7846                 Datum           d;
7847                 char       *val;
7848                 bool            isnull;
7849
7850                 d = array_ref(array, 1, &i,
7851                                           -1 /* varlenarray */ ,
7852                                           -1 /* TEXT's typlen */ ,
7853                                           false /* TEXT's typbyval */ ,
7854                                           'i' /* TEXT's typalign */ ,
7855                                           &isnull);
7856                 if (isnull)
7857                         continue;
7858                 val = TextDatumGetCString(d);
7859
7860                 /* ignore entry if it's what we want to delete */
7861                 if (strncmp(val, name, strlen(name)) == 0
7862                         && val[strlen(name)] == '=')
7863                         continue;
7864
7865                 /* else add it to the output array */
7866                 if (newarray)
7867                         newarray = array_set(newarray, 1, &index,
7868                                                                  d,
7869                                                                  false,
7870                                                                  -1 /* varlenarray */ ,
7871                                                                  -1 /* TEXT's typlen */ ,
7872                                                                  false /* TEXT's typbyval */ ,
7873                                                                  'i' /* TEXT's typalign */ );
7874                 else
7875                         newarray = construct_array(&d, 1,
7876                                                                            TEXTOID,
7877                                                                            -1, false, 'i');
7878
7879                 index++;
7880         }
7881
7882         return newarray;
7883 }
7884
7885
7886 /*
7887  * Given a GUC array, delete all settings from it that our permission
7888  * level allows: if superuser, delete them all; if regular user, only
7889  * those that are PGC_USERSET
7890  */
7891 ArrayType *
7892 GUCArrayReset(ArrayType *array)
7893 {
7894         ArrayType  *newarray;
7895         int                     i;
7896         int                     index;
7897
7898         /* if array is currently null, nothing to do */
7899         if (!array)
7900                 return NULL;
7901
7902         /* if we're superuser, we can delete everything, so just do it */
7903         if (superuser())
7904                 return NULL;
7905
7906         newarray = NULL;
7907         index = 1;
7908
7909         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7910         {
7911                 Datum           d;
7912                 char       *val;
7913                 char       *eqsgn;
7914                 bool            isnull;
7915
7916                 d = array_ref(array, 1, &i,
7917                                           -1 /* varlenarray */ ,
7918                                           -1 /* TEXT's typlen */ ,
7919                                           false /* TEXT's typbyval */ ,
7920                                           'i' /* TEXT's typalign */ ,
7921                                           &isnull);
7922                 if (isnull)
7923                         continue;
7924                 val = TextDatumGetCString(d);
7925
7926                 eqsgn = strchr(val, '=');
7927                 *eqsgn = '\0';
7928
7929                 /* skip if we have permission to delete it */
7930                 if (validate_option_array_item(val, NULL, true))
7931                         continue;
7932
7933                 /* else add it to the output array */
7934                 if (newarray)
7935                         newarray = array_set(newarray, 1, &index,
7936                                                                  d,
7937                                                                  false,
7938                                                                  -1 /* varlenarray */ ,
7939                                                                  -1 /* TEXT's typlen */ ,
7940                                                                  false /* TEXT's typbyval */ ,
7941                                                                  'i' /* TEXT's typalign */ );
7942                 else
7943                         newarray = construct_array(&d, 1,
7944                                                                            TEXTOID,
7945                                                                            -1, false, 'i');
7946
7947                 index++;
7948                 pfree(val);
7949         }
7950
7951         return newarray;
7952 }
7953
7954 /*
7955  * Validate a proposed option setting for GUCArrayAdd/Delete/Reset.
7956  *
7957  * name is the option name.  value is the proposed value for the Add case,
7958  * or NULL for the Delete/Reset cases.  If skipIfNoPermissions is true, it's
7959  * not an error to have no permissions to set the option.
7960  *
7961  * Returns TRUE if OK, FALSE if skipIfNoPermissions is true and user does not
7962  * have permission to change this option (all other error cases result in an
7963  * error being thrown).
7964  */
7965 static bool
7966 validate_option_array_item(const char *name, const char *value,
7967                                                    bool skipIfNoPermissions)
7968
7969 {
7970         struct config_generic *gconf;
7971
7972         /*
7973          * There are three cases to consider:
7974          *
7975          * name is a known GUC variable.  Check the value normally, check
7976          * permissions normally (ie, allow if variable is USERSET, or if it's
7977          * SUSET and user is superuser).
7978          *
7979          * name is not known, but exists or can be created as a placeholder (i.e.,
7980          * it has a prefixed name).  We allow this case if you're a superuser,
7981          * otherwise not.  Superusers are assumed to know what they're doing.
7982          * We can't allow it for other users, because when the placeholder is
7983          * resolved it might turn out to be a SUSET variable;
7984          * define_custom_variable assumes we checked that.
7985          *
7986          * name is not known and can't be created as a placeholder.  Throw error,
7987          * unless skipIfNoPermissions is true, in which case return FALSE.
7988          */
7989         gconf = find_option(name, true, WARNING);
7990         if (!gconf)
7991         {
7992                 /* not known, failed to make a placeholder */
7993                 if (skipIfNoPermissions)
7994                         return false;
7995                 ereport(ERROR,
7996                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
7997                                  errmsg("unrecognized configuration parameter \"%s\"",
7998                                                 name)));
7999         }
8000
8001         if (gconf->flags & GUC_CUSTOM_PLACEHOLDER)
8002         {
8003                 /*
8004                  * We cannot do any meaningful check on the value, so only permissions
8005                  * are useful to check.
8006                  */
8007                 if (superuser())
8008                         return true;
8009                 if (skipIfNoPermissions)
8010                         return false;
8011                 ereport(ERROR,
8012                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
8013                                  errmsg("permission denied to set parameter \"%s\"", name)));
8014         }
8015
8016         /* manual permissions check so we can avoid an error being thrown */
8017         if (gconf->context == PGC_USERSET)
8018                  /* ok */ ;
8019         else if (gconf->context == PGC_SUSET && superuser())
8020                  /* ok */ ;
8021         else if (skipIfNoPermissions)
8022                 return false;
8023         /* if a permissions error should be thrown, let set_config_option do it */
8024
8025         /* test for permissions and valid option value */
8026         (void) set_config_option(name, value,
8027                                                          superuser() ? PGC_SUSET : PGC_USERSET,
8028                                                          PGC_S_TEST, GUC_ACTION_SET, false, 0);
8029
8030         return true;
8031 }
8032
8033
8034 /*
8035  * Called by check_hooks that want to override the normal
8036  * ERRCODE_INVALID_PARAMETER_VALUE SQLSTATE for check hook failures.
8037  *
8038  * Note that GUC_check_errmsg() etc are just macros that result in a direct
8039  * assignment to the associated variables.      That is ugly, but forced by the
8040  * limitations of C's macro mechanisms.
8041  */
8042 void
8043 GUC_check_errcode(int sqlerrcode)
8044 {
8045         GUC_check_errcode_value = sqlerrcode;
8046 }
8047
8048
8049 /*
8050  * Convenience functions to manage calling a variable's check_hook.
8051  * These mostly take care of the protocol for letting check hooks supply
8052  * portions of the error report on failure.
8053  */
8054
8055 static bool
8056 call_bool_check_hook(struct config_bool * conf, bool *newval, void **extra,
8057                                          GucSource source, int elevel)
8058 {
8059         /* Quick success if no hook */
8060         if (!conf->check_hook)
8061                 return true;
8062
8063         /* Reset variables that might be set by hook */
8064         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8065         GUC_check_errmsg_string = NULL;
8066         GUC_check_errdetail_string = NULL;
8067         GUC_check_errhint_string = NULL;
8068
8069         if (!(*conf->check_hook) (newval, extra, source))
8070         {
8071                 ereport(elevel,
8072                                 (errcode(GUC_check_errcode_value),
8073                                  GUC_check_errmsg_string ?
8074                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8075                                  errmsg("invalid value for parameter \"%s\": %d",
8076                                                 conf->gen.name, (int) *newval),
8077                                  GUC_check_errdetail_string ?
8078                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8079                                  GUC_check_errhint_string ?
8080                                  errhint("%s", GUC_check_errhint_string) : 0));
8081                 /* Flush any strings created in ErrorContext */
8082                 FlushErrorState();
8083                 return false;
8084         }
8085
8086         return true;
8087 }
8088
8089 static bool
8090 call_int_check_hook(struct config_int * conf, int *newval, void **extra,
8091                                         GucSource source, int elevel)
8092 {
8093         /* Quick success if no hook */
8094         if (!conf->check_hook)
8095                 return true;
8096
8097         /* Reset variables that might be set by hook */
8098         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8099         GUC_check_errmsg_string = NULL;
8100         GUC_check_errdetail_string = NULL;
8101         GUC_check_errhint_string = NULL;
8102
8103         if (!(*conf->check_hook) (newval, extra, source))
8104         {
8105                 ereport(elevel,
8106                                 (errcode(GUC_check_errcode_value),
8107                                  GUC_check_errmsg_string ?
8108                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8109                                  errmsg("invalid value for parameter \"%s\": %d",
8110                                                 conf->gen.name, *newval),
8111                                  GUC_check_errdetail_string ?
8112                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8113                                  GUC_check_errhint_string ?
8114                                  errhint("%s", GUC_check_errhint_string) : 0));
8115                 /* Flush any strings created in ErrorContext */
8116                 FlushErrorState();
8117                 return false;
8118         }
8119
8120         return true;
8121 }
8122
8123 static bool
8124 call_real_check_hook(struct config_real * conf, double *newval, void **extra,
8125                                          GucSource source, int elevel)
8126 {
8127         /* Quick success if no hook */
8128         if (!conf->check_hook)
8129                 return true;
8130
8131         /* Reset variables that might be set by hook */
8132         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8133         GUC_check_errmsg_string = NULL;
8134         GUC_check_errdetail_string = NULL;
8135         GUC_check_errhint_string = NULL;
8136
8137         if (!(*conf->check_hook) (newval, extra, source))
8138         {
8139                 ereport(elevel,
8140                                 (errcode(GUC_check_errcode_value),
8141                                  GUC_check_errmsg_string ?
8142                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8143                                  errmsg("invalid value for parameter \"%s\": %g",
8144                                                 conf->gen.name, *newval),
8145                                  GUC_check_errdetail_string ?
8146                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8147                                  GUC_check_errhint_string ?
8148                                  errhint("%s", GUC_check_errhint_string) : 0));
8149                 /* Flush any strings created in ErrorContext */
8150                 FlushErrorState();
8151                 return false;
8152         }
8153
8154         return true;
8155 }
8156
8157 static bool
8158 call_string_check_hook(struct config_string * conf, char **newval, void **extra,
8159                                            GucSource source, int elevel)
8160 {
8161         /* Quick success if no hook */
8162         if (!conf->check_hook)
8163                 return true;
8164
8165         /* Reset variables that might be set by hook */
8166         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8167         GUC_check_errmsg_string = NULL;
8168         GUC_check_errdetail_string = NULL;
8169         GUC_check_errhint_string = NULL;
8170
8171         if (!(*conf->check_hook) (newval, extra, source))
8172         {
8173                 ereport(elevel,
8174                                 (errcode(GUC_check_errcode_value),
8175                                  GUC_check_errmsg_string ?
8176                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8177                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
8178                                                 conf->gen.name, *newval ? *newval : ""),
8179                                  GUC_check_errdetail_string ?
8180                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8181                                  GUC_check_errhint_string ?
8182                                  errhint("%s", GUC_check_errhint_string) : 0));
8183                 /* Flush any strings created in ErrorContext */
8184                 FlushErrorState();
8185                 return false;
8186         }
8187
8188         return true;
8189 }
8190
8191 static bool
8192 call_enum_check_hook(struct config_enum * conf, int *newval, void **extra,
8193                                          GucSource source, int elevel)
8194 {
8195         /* Quick success if no hook */
8196         if (!conf->check_hook)
8197                 return true;
8198
8199         /* Reset variables that might be set by hook */
8200         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8201         GUC_check_errmsg_string = NULL;
8202         GUC_check_errdetail_string = NULL;
8203         GUC_check_errhint_string = NULL;
8204
8205         if (!(*conf->check_hook) (newval, extra, source))
8206         {
8207                 ereport(elevel,
8208                                 (errcode(GUC_check_errcode_value),
8209                                  GUC_check_errmsg_string ?
8210                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8211                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
8212                                                 conf->gen.name,
8213                                                 config_enum_lookup_by_value(conf, *newval)),
8214                                  GUC_check_errdetail_string ?
8215                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8216                                  GUC_check_errhint_string ?
8217                                  errhint("%s", GUC_check_errhint_string) : 0));
8218                 /* Flush any strings created in ErrorContext */
8219                 FlushErrorState();
8220                 return false;
8221         }
8222
8223         return true;
8224 }
8225
8226
8227 /*
8228  * check_hook, assign_hook and show_hook subroutines
8229  */
8230
8231 static bool
8232 check_log_destination(char **newval, void **extra, GucSource source)
8233 {
8234         char       *rawstring;
8235         List       *elemlist;
8236         ListCell   *l;
8237         int                     newlogdest = 0;
8238         int                *myextra;
8239
8240         /* Need a modifiable copy of string */
8241         rawstring = pstrdup(*newval);
8242
8243         /* Parse string into list of identifiers */
8244         if (!SplitIdentifierString(rawstring, ',', &elemlist))
8245         {
8246                 /* syntax error in list */
8247                 GUC_check_errdetail("List syntax is invalid.");
8248                 pfree(rawstring);
8249                 list_free(elemlist);
8250                 return false;
8251         }
8252
8253         foreach(l, elemlist)
8254         {
8255                 char       *tok = (char *) lfirst(l);
8256
8257                 if (pg_strcasecmp(tok, "stderr") == 0)
8258                         newlogdest |= LOG_DESTINATION_STDERR;
8259                 else if (pg_strcasecmp(tok, "csvlog") == 0)
8260                         newlogdest |= LOG_DESTINATION_CSVLOG;
8261 #ifdef HAVE_SYSLOG
8262                 else if (pg_strcasecmp(tok, "syslog") == 0)
8263                         newlogdest |= LOG_DESTINATION_SYSLOG;
8264 #endif
8265 #ifdef WIN32
8266                 else if (pg_strcasecmp(tok, "eventlog") == 0)
8267                         newlogdest |= LOG_DESTINATION_EVENTLOG;
8268 #endif
8269                 else
8270                 {
8271                         GUC_check_errdetail("Unrecognized key word: \"%s\".", tok);
8272                         pfree(rawstring);
8273                         list_free(elemlist);
8274                         return false;
8275                 }
8276         }
8277
8278         pfree(rawstring);
8279         list_free(elemlist);
8280
8281         myextra = (int *) guc_malloc(ERROR, sizeof(int));
8282         *myextra = newlogdest;
8283         *extra = (void *) myextra;
8284
8285         return true;
8286 }
8287
8288 static void
8289 assign_log_destination(const char *newval, void *extra)
8290 {
8291         Log_destination = *((int *) extra);
8292 }
8293
8294 static void
8295 assign_syslog_facility(int newval, void *extra)
8296 {
8297 #ifdef HAVE_SYSLOG
8298         set_syslog_parameters(syslog_ident_str ? syslog_ident_str : "postgres",
8299                                                   newval);
8300 #endif
8301         /* Without syslog support, just ignore it */
8302 }
8303
8304 static void
8305 assign_syslog_ident(const char *newval, void *extra)
8306 {
8307 #ifdef HAVE_SYSLOG
8308         set_syslog_parameters(newval, syslog_facility);
8309 #endif
8310         /* Without syslog support, it will always be set to "none", so ignore */
8311 }
8312
8313
8314 static void
8315 assign_session_replication_role(int newval, void *extra)
8316 {
8317         /*
8318          * Must flush the plan cache when changing replication role; but don't
8319          * flush unnecessarily.
8320          */
8321         if (SessionReplicationRole != newval)
8322                 ResetPlanCache();
8323 }
8324
8325 static bool
8326 check_temp_buffers(int *newval, void **extra, GucSource source)
8327 {
8328         /*
8329          * Once local buffers have been initialized, it's too late to change this.
8330          */
8331         if (NLocBuffer && NLocBuffer != *newval)
8332         {
8333                 GUC_check_errdetail("\"temp_buffers\" cannot be changed after any temporary tables have been accessed in the session.");
8334                 return false;
8335         }
8336         return true;
8337 }
8338
8339 static bool
8340 check_phony_autocommit(bool *newval, void **extra, GucSource source)
8341 {
8342         if (!*newval)
8343         {
8344                 GUC_check_errcode(ERRCODE_FEATURE_NOT_SUPPORTED);
8345                 GUC_check_errmsg("SET AUTOCOMMIT TO OFF is no longer supported");
8346                 return false;
8347         }
8348         return true;
8349 }
8350
8351 static bool
8352 check_debug_assertions(bool *newval, void **extra, GucSource source)
8353 {
8354 #ifndef USE_ASSERT_CHECKING
8355         if (*newval)
8356         {
8357                 GUC_check_errmsg("assertion checking is not supported by this build");
8358                 return false;
8359         }
8360 #endif
8361         return true;
8362 }
8363
8364 static bool
8365 check_bonjour(bool *newval, void **extra, GucSource source)
8366 {
8367 #ifndef USE_BONJOUR
8368         if (*newval)
8369         {
8370                 GUC_check_errmsg("Bonjour is not supported by this build");
8371                 return false;
8372         }
8373 #endif
8374         return true;
8375 }
8376
8377 static bool
8378 check_ssl(bool *newval, void **extra, GucSource source)
8379 {
8380 #ifndef USE_SSL
8381         if (*newval)
8382         {
8383                 GUC_check_errmsg("SSL is not supported by this build");
8384                 return false;
8385         }
8386 #endif
8387         return true;
8388 }
8389
8390 static bool
8391 check_stage_log_stats(bool *newval, void **extra, GucSource source)
8392 {
8393         if (*newval && log_statement_stats)
8394         {
8395                 GUC_check_errdetail("Cannot enable parameter when \"log_statement_stats\" is true.");
8396                 return false;
8397         }
8398         return true;
8399 }
8400
8401 static bool
8402 check_log_stats(bool *newval, void **extra, GucSource source)
8403 {
8404         if (*newval &&
8405                 (log_parser_stats || log_planner_stats || log_executor_stats))
8406         {
8407                 GUC_check_errdetail("Cannot enable \"log_statement_stats\" when "
8408                                                         "\"log_parser_stats\", \"log_planner_stats\", "
8409                                                         "or \"log_executor_stats\" is true.");
8410                 return false;
8411         }
8412         return true;
8413 }
8414
8415 static bool
8416 check_canonical_path(char **newval, void **extra, GucSource source)
8417 {
8418         /*
8419          * Since canonicalize_path never enlarges the string, we can just modify
8420          * newval in-place.  But watch out for NULL, which is the default value
8421          * for external_pid_file.
8422          */
8423         if (*newval)
8424                 canonicalize_path(*newval);
8425         return true;
8426 }
8427
8428 static bool
8429 check_timezone_abbreviations(char **newval, void **extra, GucSource source)
8430 {
8431         /*
8432          * The boot_val given above for timezone_abbreviations is NULL. When we
8433          * see this we just do nothing.  If this value isn't overridden from the
8434          * config file then pg_timezone_abbrev_initialize() will eventually
8435          * replace it with "Default".  This hack has two purposes: to avoid
8436          * wasting cycles loading values that might soon be overridden from the
8437          * config file, and to avoid trying to read the timezone abbrev files
8438          * during InitializeGUCOptions().  The latter doesn't work in an
8439          * EXEC_BACKEND subprocess because my_exec_path hasn't been set yet and so
8440          * we can't locate PGSHAREDIR.
8441          */
8442         if (*newval == NULL)
8443         {
8444                 Assert(source == PGC_S_DEFAULT);
8445                 return true;
8446         }
8447
8448         /* OK, load the file and produce a malloc'd TimeZoneAbbrevTable */
8449         *extra = load_tzoffsets(*newval);
8450
8451         /* tzparser.c returns NULL on failure, reporting via GUC_check_errmsg */
8452         if (!*extra)
8453                 return false;
8454
8455         return true;
8456 }
8457
8458 static void
8459 assign_timezone_abbreviations(const char *newval, void *extra)
8460 {
8461         /* Do nothing for the boot_val default of NULL */
8462         if (!extra)
8463                 return;
8464
8465         InstallTimeZoneAbbrevs((TimeZoneAbbrevTable *) extra);
8466 }
8467
8468 /*
8469  * pg_timezone_abbrev_initialize --- set default value if not done already
8470  *
8471  * This is called after initial loading of postgresql.conf.  If no
8472  * timezone_abbreviations setting was found therein, select default.
8473  * If a non-default value is already installed, nothing will happen.
8474  *
8475  * This can also be called from ProcessConfigFile to establish the default
8476  * value after a postgresql.conf entry for it is removed.
8477  */
8478 static void
8479 pg_timezone_abbrev_initialize(void)
8480 {
8481         SetConfigOption("timezone_abbreviations", "Default",
8482                                         PGC_POSTMASTER, PGC_S_DYNAMIC_DEFAULT);
8483 }
8484
8485 static const char *
8486 show_archive_command(void)
8487 {
8488         if (XLogArchivingActive())
8489                 return XLogArchiveCommand;
8490         else
8491                 return "(disabled)";
8492 }
8493
8494 static void
8495 assign_tcp_keepalives_idle(int newval, void *extra)
8496 {
8497         /*
8498          * The kernel API provides no way to test a value without setting it; and
8499          * once we set it we might fail to unset it.  So there seems little point
8500          * in fully implementing the check-then-assign GUC API for these
8501          * variables.  Instead we just do the assignment on demand.  pqcomm.c
8502          * reports any problems via elog(LOG).
8503          *
8504          * This approach means that the GUC value might have little to do with the
8505          * actual kernel value, so we use a show_hook that retrieves the kernel
8506          * value rather than trusting GUC's copy.
8507          */
8508         (void) pq_setkeepalivesidle(newval, MyProcPort);
8509 }
8510
8511 static const char *
8512 show_tcp_keepalives_idle(void)
8513 {
8514         /* See comments in assign_tcp_keepalives_idle */
8515         static char nbuf[16];
8516
8517         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivesidle(MyProcPort));
8518         return nbuf;
8519 }
8520
8521 static void
8522 assign_tcp_keepalives_interval(int newval, void *extra)
8523 {
8524         /* See comments in assign_tcp_keepalives_idle */
8525         (void) pq_setkeepalivesinterval(newval, MyProcPort);
8526 }
8527
8528 static const char *
8529 show_tcp_keepalives_interval(void)
8530 {
8531         /* See comments in assign_tcp_keepalives_idle */
8532         static char nbuf[16];
8533
8534         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivesinterval(MyProcPort));
8535         return nbuf;
8536 }
8537
8538 static void
8539 assign_tcp_keepalives_count(int newval, void *extra)
8540 {
8541         /* See comments in assign_tcp_keepalives_idle */
8542         (void) pq_setkeepalivescount(newval, MyProcPort);
8543 }
8544
8545 static const char *
8546 show_tcp_keepalives_count(void)
8547 {
8548         /* See comments in assign_tcp_keepalives_idle */
8549         static char nbuf[16];
8550
8551         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivescount(MyProcPort));
8552         return nbuf;
8553 }
8554
8555 static bool
8556 check_maxconnections(int *newval, void **extra, GucSource source)
8557 {
8558         if (*newval + autovacuum_max_workers + 1 > MAX_BACKENDS)
8559                 return false;
8560         return true;
8561 }
8562
8563 static void
8564 assign_maxconnections(int newval, void *extra)
8565 {
8566         MaxBackends = newval + autovacuum_max_workers + 1;
8567 }
8568
8569 static bool
8570 check_autovacuum_max_workers(int *newval, void **extra, GucSource source)
8571 {
8572         if (MaxConnections + *newval + 1 > MAX_BACKENDS)
8573                 return false;
8574         return true;
8575 }
8576
8577 static void
8578 assign_autovacuum_max_workers(int newval, void *extra)
8579 {
8580         MaxBackends = MaxConnections + newval + 1;
8581 }
8582
8583 static bool
8584 check_effective_io_concurrency(int *newval, void **extra, GucSource source)
8585 {
8586 #ifdef USE_PREFETCH
8587         double          new_prefetch_pages = 0.0;
8588         int                     i;
8589
8590         /*----------
8591          * The user-visible GUC parameter is the number of drives (spindles),
8592          * which we need to translate to a number-of-pages-to-prefetch target.
8593          * The target value is stashed in *extra and then assigned to the actual
8594          * variable by assign_effective_io_concurrency.
8595          *
8596          * The expected number of prefetch pages needed to keep N drives busy is:
8597          *
8598          * drives |   I/O requests
8599          * -------+----------------
8600          *              1 |   1
8601          *              2 |   2/1 + 2/2 = 3
8602          *              3 |   3/1 + 3/2 + 3/3 = 5 1/2
8603          *              4 |   4/1 + 4/2 + 4/3 + 4/4 = 8 1/3
8604          *              n |   n * H(n)
8605          *
8606          * This is called the "coupon collector problem" and H(n) is called the
8607          * harmonic series.  This could be approximated by n * ln(n), but for
8608          * reasonable numbers of drives we might as well just compute the series.
8609          *
8610          * Alternatively we could set the target to the number of pages necessary
8611          * so that the expected number of active spindles is some arbitrary
8612          * percentage of the total.  This sounds the same but is actually slightly
8613          * different.  The result ends up being ln(1-P)/ln((n-1)/n) where P is
8614          * that desired fraction.
8615          *
8616          * Experimental results show that both of these formulas aren't aggressive
8617          * enough, but we don't really have any better proposals.
8618          *
8619          * Note that if *newval = 0 (disabled), we must set target = 0.
8620          *----------
8621          */
8622
8623         for (i = 1; i <= *newval; i++)
8624                 new_prefetch_pages += (double) *newval / (double) i;
8625
8626         /* This range check shouldn't fail, but let's be paranoid */
8627         if (new_prefetch_pages >= 0.0 && new_prefetch_pages < (double) INT_MAX)
8628         {
8629                 int                *myextra = (int *) guc_malloc(ERROR, sizeof(int));
8630
8631                 *myextra = (int) rint(new_prefetch_pages);
8632                 *extra = (void *) myextra;
8633
8634                 return true;
8635         }
8636         else
8637                 return false;
8638 #else
8639         return true;
8640 #endif   /* USE_PREFETCH */
8641 }
8642
8643 static void
8644 assign_effective_io_concurrency(int newval, void *extra)
8645 {
8646 #ifdef USE_PREFETCH
8647         target_prefetch_pages = *((int *) extra);
8648 #endif   /* USE_PREFETCH */
8649 }
8650
8651 static void
8652 assign_pgstat_temp_directory(const char *newval, void *extra)
8653 {
8654         /* check_canonical_path already canonicalized newval for us */
8655         char       *tname;
8656         char       *fname;
8657
8658         tname = guc_malloc(ERROR, strlen(newval) + 12);         /* /pgstat.tmp */
8659         sprintf(tname, "%s/pgstat.tmp", newval);
8660         fname = guc_malloc(ERROR, strlen(newval) + 13);         /* /pgstat.stat */
8661         sprintf(fname, "%s/pgstat.stat", newval);
8662
8663         if (pgstat_stat_tmpname)
8664                 free(pgstat_stat_tmpname);
8665         pgstat_stat_tmpname = tname;
8666         if (pgstat_stat_filename)
8667                 free(pgstat_stat_filename);
8668         pgstat_stat_filename = fname;
8669 }
8670
8671 static bool
8672 check_application_name(char **newval, void **extra, GucSource source)
8673 {
8674         /* Only allow clean ASCII chars in the application name */
8675         char       *p;
8676
8677         for (p = *newval; *p; p++)
8678         {
8679                 if (*p < 32 || *p > 126)
8680                         *p = '?';
8681         }
8682
8683         return true;
8684 }
8685
8686 static void
8687 assign_application_name(const char *newval, void *extra)
8688 {
8689         /* Update the pg_stat_activity view */
8690         pgstat_report_appname(newval);
8691 }
8692
8693 static const char *
8694 show_unix_socket_permissions(void)
8695 {
8696         static char buf[8];
8697
8698         snprintf(buf, sizeof(buf), "%04o", Unix_socket_permissions);
8699         return buf;
8700 }
8701
8702 static const char *
8703 show_log_file_mode(void)
8704 {
8705         static char buf[8];
8706
8707         snprintf(buf, sizeof(buf), "%04o", Log_file_mode);
8708         return buf;
8709 }
8710
8711 #include "guc-file.c"